Define pseudonatural transformations

This is based on an email from Mike Shulman.

Compared with the pain of pseduofunctors, this one is surprisingly fast
and (comparatively) lacking in pain.

I'm not at all confident that I got it right, given that
[nCatLab](http://ncatlab.org/nlab/show/pseudonatural+transformation#definition)
mentions three laws rather than just one (respect for composition,
respect for units, and naturality).  But I guess if it gives me enough
rope to define lax comma categories, and if I can show that every
natural transformation between functors to Cat gives rise to a
pseudonatural transformation between the corresponding pseudofunctors, I
might not care?

After    | File Name                                                          | Before   || Change
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9m21.00s | Total                                                              | 9m12.75s || +0m08.25s
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0m06.60s | categories/PseudonaturalTransformation/Core                        |   N/A    || +0m06.59s
1m46.34s | categories/Comma/ProjectionFunctors                                | 1m46.53s || -0m00.18s
0m33.65s | categories/Adjoint/Composition/AssociativityLaw                    | 0m34.37s || -0m00.71s
0m25.25s | categories/Grothendieck/PseudofunctorToCat                         | 0m25.27s || -0m00.01s
0m21.69s | categories/Adjoint/HomCoercions                                    | 0m21.40s || +0m00.29s
0m16.96s | categories/ExponentialLaws/Law4/Functors                           | 0m16.75s || +0m00.21s
0m16.81s | categories/Adjoint/UnitCounitCoercions                             | 0m17.80s || -0m00.99s
0m15.71s | categories/Comma/InducedFunctors                                   | 0m15.87s || -0m00.15s
0m15.66s | categories/FunctorCategory/Dual                                    | 0m15.95s || -0m00.28s
0m12.74s | hit/Flattening                                                     | 0m12.56s || +0m00.17s
0m12.67s | categories/Functor/Pointwise/Properties                            | 0m12.13s || +0m00.53s
0m12.59s | categories/Pseudofunctor/Core                                      | 0m12.42s || +0m00.16s
0m12.36s | categories/Adjoint/Dual                                            | 0m11.81s || +0m00.54s
0m11.97s | categories/Adjoint/Composition/Core                                | 0m12.40s || -0m00.42s
0m11.44s | categories/Adjoint/Composition/IdentityLaws                        | 0m11.00s || +0m00.43s
0m10.86s | categories/Pseudofunctor/FromFunctor                               | 0m10.68s || +0m00.17s
0m08.66s | categories/ExponentialLaws/Law1/Law                                | 0m08.33s || +0m00.33s
0m08.61s | categories/Functor/Prod/Universal                                  | 0m07.65s || +0m00.95s
0m08.34s | categories/Yoneda                                                  | 0m07.90s || +0m00.43s
0m07.84s | categories/GroupoidCategory/Morphisms                              | 0m07.46s || +0m00.37s
0m07.28s | hit/Connectedness                                                  | 0m07.08s || +0m00.20s
0m07.16s | categories/UniversalProperties                                     | 0m07.40s || -0m00.24s
0m06.50s | categories/Structure/IdentityPrinciple                             | 0m06.52s || -0m00.01s
0m06.50s | categories/Comma/Dual                                              | 0m06.77s || -0m00.26s
0m06.37s | categories/Adjoint/Paths                                           | 0m06.58s || -0m00.20s
0m06.29s | categories/Adjoint/UnitCounit                                      | 0m06.23s || +0m00.05s
0m06.05s | categories/Functor/Paths                                           | 0m05.69s || +0m00.35s
0m05.45s | categories/Category/Morphisms                                      | 0m05.68s || -0m00.22s
0m05.24s | EquivalenceVarieties                                               | 0m05.32s || -0m00.08s
0m05.21s | categories/Functor/Sum                                             | 0m05.33s || -0m00.12s
0m04.86s | categories/ExponentialLaws/Law2/Functors                           | 0m04.76s || +0m00.10s
0m04.45s | categories/DualFunctor                                             | 0m04.69s || -0m00.24s
0m04.38s | categories/Category/Sigma/OnMorphisms                              | 0m04.44s || -0m00.06s
0m03.85s | categories/ProductLaws                                             | 0m03.67s || +0m00.18s
0m03.56s | categories/Structure/Core                                          | 0m03.67s || -0m00.10s
0m03.27s | types/ObjectClassifier                                             | 0m03.34s || -0m00.06s
0m03.01s | types/Sigma                                                        | 0m03.14s || -0m00.13s
0m02.95s | HSet                                                               | 0m03.06s || -0m00.10s
0m02.90s | categories/Functor/Composition/Functorial/Attributes               | 0m03.01s || -0m00.10s
0m02.87s | categories/Functor/Prod/Functorial                                 | 0m02.82s || +0m00.05s
0m02.84s | categories/FunctorCategory/Functorial                              | 0m02.86s || -0m00.02s
0m02.72s | categories/Adjoint/UniversalMorphisms                              | 0m02.76s || -0m00.03s
0m02.71s | HProp                                                              | 0m02.71s || +0m00.00s
0m02.54s | Equivalences                                                       | 0m02.58s || -0m00.04s
0m02.44s | categories/Grothendieck/ToSet                                      | 0m02.40s || +0m00.04s
0m02.31s | categories/Functor/Attributes                                      | 0m02.34s || -0m00.02s
0m02.20s | categories/Category/Sum                                            | 0m02.25s || -0m00.04s
0m02.17s | categories/Category/Sigma/Core                                     | 0m01.91s || +0m00.26s
0m02.14s | categories/Comma/Core                                              | 0m02.12s || +0m00.02s
0m02.05s | categories/NaturalTransformation/Isomorphisms                      | 0m01.94s || +0m00.10s
0m01.93s | PathGroupoids                                                      | 0m01.88s || +0m00.05s
0m01.84s | categories/NaturalTransformation/Dual                              | 0m01.94s || -0m00.09s
0m01.83s | types/Record                                                       | 0m01.99s || -0m00.15s
0m01.77s | categories/FunctorCategory/Morphisms                               | 0m01.62s || +0m00.14s
0m01.70s | categories/HomFunctor                                              | 0m01.76s || -0m00.06s
0m01.65s | categories/NaturalTransformation/Paths                             | 0m01.60s || +0m00.04s
0m01.35s | categories/Category/Prod                                           | 0m01.34s || +0m00.01s
0m01.34s | categories/NaturalTransformation/Pointwise                         | 0m01.36s || -0m00.02s
0m01.28s | types/Prod                                                         | 0m01.37s || -0m00.09s
0m01.22s | categories/Category/Sigma/OnObjects                                | 0m01.24s || -0m00.02s
0m01.15s | categories/NaturalTransformation/Composition/Laws                  | 0m01.19s || -0m00.04s
0m01.14s | categories/Limits/Core                                             | 0m01.14s || +0m00.00s
0m01.12s | categories/Functor/Composition/Functorial/Core                     | 0m01.18s || -0m00.05s
0m01.12s | hit/Spheres                                                        | 0m00.84s || +0m00.28s
0m01.08s | categories/Functor/Pointwise                                       | 0m01.01s || +0m00.07s
0m01.04s | hit/epi                                                            | 0m00.89s || +0m00.15s
0m01.02s | categories/ExponentialLaws/Law  N/A                                | 0m01.02s || +0m00.00s
0m01.01s | categories/ExponentialLaws/Law1/Functors                           | 0m00.98s || +0m00.03s
0m00.98s | categories/CategoryOfSections/Core                                 | 0m01.09s || -0m00.11s
0m00.94s | categories/Functor/Prod                                            | 0m00.94s || +0m00.00s
0m00.93s | categories/NaturalTransformation/Prod                              | 0m00.97s || -0m00.03s
0m00.88s | types/Paths                                                        | 0m00.90s || -0m00.02s
0m00.88s | contrib/HoTTBookExercises                                          | 0m01.00s || -0m00.12s
0m00.80s | categories/SetCategory/Morphisms                                   | 0m00.80s || +0m00.00s
0m00.73s | contrib/HoTTBook                                                   | 0m00.68s || +0m00.04s
0m00.68s | types/Universe                                                     | 0m00.63s || +0m00.05s
0m00.68s | hit/Suspension                                                     | 0m00.60s || +0m00.08s
0m00.67s | types/Sum                                                          | 0m00.60s || +0m00.07s
0m00.65s | categories/NaturalTransformation/Composition/Core                  | 0m00.64s || +0m00.01s
0m00.61s | categories/InitialTerminalCategory                                 | 0m00.69s || -0m00.07s
0m00.60s | UnivalenceImpliesFunext                                            | 0m00.64s || -0m00.04s
0m00.58s | Trunc                                                              | 0m00.62s || -0m00.04s
0m00.58s | hit/quotient                                                       | 0m00.55s || +0m00.02s
0m00.57s | categories/categories                                              | 0m00.56s || +0m00.00s
0m00.56s | Functorish                                                         | 0m00.58s || -0m00.01s
0m00.56s | categories/NaturalTransformation/Sum                               | 0m00.60s || -0m00.03s
0m00.56s | categories/Comma/Projection                                        | 0m00.54s || +0m00.02s
0m00.54s | categories/Limits/Functors                                         | 0m00.48s || +0m00.06s
0m00.54s | categories/Functor/Composition/Laws                                | 0m00.52s || +0m00.02s
0m00.49s | hit/Circle                                                         | 0m00.53s || -0m00.04s
0m00.48s | categories/KanExtensions/Functors                                  | 0m00.47s || +0m00.01s
0m00.47s | categories/Cat/Core                                                | 0m00.42s || +0m00.04s
0m00.44s | categories/ExponentialLaws/Law3/Functors                           | 0m00.46s || -0m00.02s
0m00.44s | Tactics                                                            | 0m00.50s || -0m00.06s
0m00.44s | types/Forall                                                       | 0m00.46s || -0m00.02s
0m00.39s | categories/Functor/Dual                                            | 0m00.34s || +0m00.04s
0m00.37s | categories/IndiscreteCategory                                      | 0m00.39s || -0m00.02s
0m00.37s | Fibrations                                                         | 0m00.37s || +0m00.00s
0m00.36s | categories/FundamentalPreGroupoidCategory                          | 0m00.32s || +0m00.03s
0m00.36s | TruncType                                                          | 0m00.32s || +0m00.03s
0m00.34s | categories/NaturalTransformation/Composition/Functorial            | 0m00.33s || +0m00.01s
0m00.33s | categories/HomotopyPreCategory                                     | 0m00.29s || +0m00.04s
0m00.33s | categories/NaturalTransformation/Identity                          | 0m00.42s || -0m00.08s
0m00.31s | categories/KanExtensions/Core                                      | 0m00.34s || -0m00.03s
0m00.30s | categories/Functor/Functor                                         | 0m00.30s || +0m00.00s
0m00.30s | categories/Cat/Morphisms                                           | 0m00.25s || +0m00.04s
0m00.29s | categories/ExponentialLaws/ExponentialLaws                         | 0m00.29s || +0m00.00s
0m00.29s | categories/Adjoint/Hom                                             | 0m00.27s || +0m00.01s
0m00.29s | hit/minus1Trunc                                                    | 0m00.32s || -0m00.03s
0m00.26s | types/Arrow                                                        | 0m00.26s || +0m00.00s
0m00.25s | categories/NaturalTransformation/NaturalTransformation             | 0m00.20s || +0m00.04s
0m00.25s | categories/Utf8                                                    | 0m00.27s || -0m00.02s
0m00.25s | categories/Notations                                               | 0m00.26s || -0m00.01s
0m00.25s | categories/Adjoint/Adjoint                                         | 0m00.24s || +0m00.01s
0m00.24s | categories/SetCategory/Functors/Functors                           | 0m00.20s || +0m00.03s
0m00.24s | categories/Category/Objects                                        | 0m00.24s || +0m00.00s
0m00.24s | categories/Functor/Composition/Core                                | 0m00.28s || -0m00.04s
0m00.24s | categories/Grothendieck/Grothendieck                               | 0m00.28s || -0m00.04s
0m00.22s | Conjugation                                                        | 0m00.19s || +0m00.03s
0m00.22s | hit/iso                                                            | 0m00.17s || +0m00.04s
0m00.22s | categories/Functor/Composition/Composition                         | 0m00.21s || +0m00.01s
0m00.22s | categories/FunctorCategory/FunctorCategory                         | 0m00.20s || +0m00.01s
0m00.22s | FunextVarieties                                                    | 0m00.23s || -0m00.01s
0m00.21s | categories/FunctorCategory/Utf8                                    | 0m00.19s || +0m00.01s
0m00.20s | categories/Profunctor/Representable                                | 0m00.16s || +0m00.04s
0m00.20s | categories/DependentProduct                                        | 0m00.20s || +0m00.00s
0m00.20s | categories/Functor/Composition/Functorial                          | 0m00.28s || -0m00.08s
0m00.20s | HoTT                                                               | 0m00.19s || +0m00.01s
0m00.20s | categories/Grothendieck/ToCat                                      | 0m00.18s || +0m00.02s
0m00.20s | categories/Comma/Comma                                             | 0m00.18s || +0m00.02s
0m00.20s | Modality                                                           | 0m00.20s || +0m00.00s
0m00.20s | categories/Pseudofunctor/Pseudofunctor                             | 0m00.18s || +0m00.02s
0m00.20s | types/Bool                                                         | 0m00.22s || -0m00.01s
0m00.20s | categories/ExponentialLaws/Law2/Law2                               | 0m00.18s || +0m00.02s
0m00.19s | categories/Limits/Limits                                           | 0m00.17s || +0m00.01s
0m00.19s | categories/Cat/Cat                                                 | 0m00.16s || +0m00.03s
0m00.19s | categories/Functor/Prod/Prod                                       | 0m00.18s || +0m00.01s
0m00.19s | categories/Category/Pi                                             | 0m00.16s || +0m00.03s
0m00.18s | categories/Comma/Utf8                                              | 0m00.18s || +0m00.00s
0m00.18s | categories/KanExtensions/KanExtensions                             | 0m00.20s || -0m00.02s
0m00.18s | categories/Category/Dual                                           | 0m00.16s || +0m00.01s
0m00.18s | categories/GroupoidCategory/Core                                   | 0m00.17s || +0m00.00s
0m00.18s | categories/NaturalTransformation/Utf8                              | 0m00.17s || +0m00.00s
0m00.18s | categories/FunctorCategory/Core                                    | 0m00.16s || +0m00.01s
0m00.17s | categories/SetCategory/Core                                        | 0m00.13s || +0m00.04s
0m00.17s | Misc                                                               | 0m00.14s || +0m00.03s
0m00.17s | hit/unique_choice                                                  | 0m00.15s || +0m00.02s
0m00.17s | categories/Functor/Notations                                       | 0m00.18s || -0m00.00s
0m00.17s | categories/NatCategory                                             | 0m00.19s || -0m00.01s
0m00.17s | categories/PseudonaturalTransformation/PseudonaturalTransformation |   N/A    || +0m00.17s
0m00.17s | categories/ExponentialLaws/Law1/Law1                               | 0m00.18s || -0m00.00s
0m00.16s | categories/Adjoint/Utf8                                            | 0m00.18s || -0m00.01s
0m00.16s | categories/NaturalTransformation/Core                              | 0m00.15s || +0m00.01s
0m00.16s | categories/Functor/Utf8                                            | 0m00.17s || -0m00.01s
0m00.16s | categories/NaturalTransformation/Notations                         | 0m00.14s || +0m00.01s
0m00.16s | categories/SetCategory/SetCategory                                 | 0m00.13s || +0m00.03s
0m00.16s | categories/Adjoint/Composition/LawsTactic                          | 0m00.15s || +0m00.01s
0m00.15s | categories/Profunctor/Core                                         | 0m00.14s || +0m00.00s
0m00.15s | categories/Structure/Structure                                     | 0m00.13s || +0m00.01s
0m00.15s | categories/Adjoint/Notations                                       | 0m00.16s || -0m00.01s
0m00.15s | categories/Comma/Notations                                         | 0m00.13s || +0m00.01s
0m00.15s | categories/Category/Category                                       | 0m00.14s || +0m00.00s
0m00.15s | categories/Adjoint/Composition/Composition                         | 0m00.16s || -0m00.01s
0m00.15s | categories/Profunctor/Identity                                     | 0m00.12s || +0m00.03s
0m00.14s | hit/Interval                                                       | 0m00.10s || +0m00.04s
0m00.14s | categories/Adjoint/Identity                                        | 0m00.13s || +0m00.01s
0m00.14s | categories/Category/Univalent                                      | 0m00.14s || +0m00.00s
0m00.14s | hit/TwoSphere                                                      | 0m00.14s || +0m00.00s
0m00.14s | Tests                                                              | 0m00.18s || -0m00.03s
0m00.14s | categories/NaturalTransformation/Composition/Composition           | 0m00.13s || +0m00.01s
0m00.14s | Overture                                                           | 0m00.14s || +0m00.00s
0m00.14s | categories/Structure/Utf8                                          | 0m00.10s || +0m00.04s
0m00.14s | categories/CategoryOfSections/CategoryOfSections                   | 0m00.13s || +0m00.01s
0m00.13s | categories/DiscreteCategory                                        | 0m00.13s || +0m00.00s
0m00.13s | categories/Category/Utf8                                           | 0m00.12s || +0m00.01s
0m00.13s | UnivalenceAxiom                                                    | 0m00.12s || +0m00.01s
0m00.13s | types/Unit                                                         | 0m00.14s || -0m00.01s
0m00.13s | categories/Functor/Pointwise/Pointwise                             | 0m00.11s || +0m00.02s
0m00.13s | hit/Truncations                                                    | 0m00.12s || +0m00.01s
0m00.13s | categories/Profunctor/Utf8                                         | 0m00.13s || +0m00.00s
0m00.12s | categories/ExponentialLaws/Law3/Law3                               | 0m00.17s || -0m00.05s
0m00.12s | categories/Adjoint/Core                                            | 0m00.10s || +0m00.01s
0m00.12s | categories/ExponentialLaws/Law4/Law4                               | 0m00.14s || -0m00.02s
0m00.12s | Pointed                                                            | 0m00.10s || +0m00.01s
0m00.12s | categories/Category/Sigma/Sigma                                    | 0m00.12s || +0m00.00s
0m00.12s | categories/FunctorCategory/Notations                               | 0m00.13s || -0m00.01s
0m00.11s | categories/GroupoidCategory/GroupoidCategory                       | 0m00.18s || -0m00.06s
0m00.11s | Contractible                                                       | 0m00.14s || -0m00.03s
0m00.11s | coq/Init/Peano                                                     | 0m00.10s || +0m00.00s
0m00.11s | categories/Functor/Core                                            | 0m00.08s || +0m00.03s
0m00.11s | categories/Profunctor/Profunctor                                   | 0m00.13s || -0m00.02s
0m00.11s | categories/Structure/Notations                                     | 0m00.08s || +0m00.03s
0m00.11s | categories/Category/Core                                           | 0m00.14s || -0m00.03s
0m00.11s | categories/Category/Notations                                      | 0m00.12s || -0m00.00s
0m00.10s | categories/Category/Strict                                         | 0m00.08s || +0m00.02s
0m00.10s | categories/Profunctor/Notations                                    | 0m00.13s || -0m00.03s
0m00.09s | categories/Category/Subcategory/Wide                               | 0m00.12s || -0m00.03s
0m00.09s | categories/Category/Subcategory/Full                               | 0m00.12s || -0m00.03s
0m00.08s | categories/Functor/Identity                                        | 0m00.05s || +0m00.03s
0m00.08s | types/UniverseLevel                                                | 0m00.08s || +0m00.00s
0m00.08s | categories/Category/Subcategory/Subcategory                        | 0m00.12s || -0m00.03s
0m00.08s | coq/Program/Tactics                                                | 0m00.05s || +0m00.03s
0m00.06s | coq/Init/Specif                                                    | 0m00.09s || -0m00.03s
0m00.06s | coq/Init/Logic_Type                                                | 0m00.05s || +0m00.00s
0m00.06s | FunextAxiom                                                        | 0m00.08s || -0m00.02s
0m00.05s | coq/Init/Datatypes                                                 | 0m00.06s || -0m00.00s
0m00.04s | coq/Init/Notations                                                 | 0m00.04s || +0m00.00s
0m00.04s | coq/Init/Prelude                                                   | 0m00.03s || +0m00.01s
0m00.04s | coq/Bool/Bool                                                      | 0m00.02s || +0m00.02s
0m00.04s | types/Empty                                                        | 0m00.08s || -0m00.04s
0m00.03s | coq/Init/Logic                                                     | 0m00.04s || -0m00.01s
0m00.03s | coq/Init/Tactics                                                   | 0m00.03s || +0m00.00s