Prove exponential laws

Unfortunately, they're still very, very slow.

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14m23.61s | Total                                        | 6m35.36s
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2m40.63s  | ExponentialLaws/Law4/Law                     | 0m00.32s
2m14.70s  | ExponentialLaws/Law3/Law                     | 0m00.29s
2m05.58s  | ExponentialLaws/Law2/Law                     | 0m02.02s
0m30.78s  | Comma/Duals                                  | 0m26.49s
0m30.12s  | Grothendieck/PseudofunctorToCat              | 0m27.36s
0m27.32s  | Adjoint/Hom                                  | 0m24.81s
0m23.61s  | Category/Equality                            | 0m23.20s
0m21.65s  | ExponentialLaws/Law4/Functors                | 0m18.97s
0m19.49s  | ExponentialLaws/Law1/Law                     | 0m16.96s
0m18.92s  | Pseudofunctor/Core                           | 0m16.89s
0m18.16s  | Adjoint/Composition                          | 0m13.64s
0m17.53s  | Adjoint/Duals                                | 0m15.27s
0m17.48s  | Functor/Pointwise/Properties                 | 0m12.88s
0m15.52s  | Pseudofunctor/FromFunctor                    | 0m13.94s
0m15.50s  | Adjoint/UniversalMorphisms                   | 0m14.90s
0m13.04s  | Adjoint/UnitCounitCoercions                  | 0m11.32s
0m11.48s  | Adjoint/Equality                             | 0m07.03s
0m11.11s  | Functor/Product                              | 0m08.09s
0m10.84s  | UniversalProperties                          | 0m10.34s
0m09.82s  | DualFunctor                                  | 0m08.27s
0m09.62s  | Comma/InducedFunctors                        | 0m08.39s
0m07.25s  | Groupoid                                     | 0m07.05s
0m07.12s  | Category/Morphisms                           | 0m07.16s
0m06.62s  | NaturalTransformation/Pointwise              | 0m04.78s
0m05.78s  | Adjoint/UnitCounit                           | 0m05.74s
0m04.78s  | Functor/Sum                                  | 0m04.70s
0m04.72s  | ExponentialLaws/Law2/Functors                | 0m04.81s
0m04.44s  | Comma/CommaCategory                          | 0m02.84s
0m04.37s  | ProductLaws                                  | 0m04.25s
0m04.25s  | Groupoid/Duals                               | 0m03.95s
0m04.17s  | Functor/Equality                             | 0m04.56s
0m03.83s  | Functor/Attributes                           | 0m03.26s
0m03.56s  | Groupoid/Functors                            | 0m03.54s
0m03.51s  | Subcategory/SigmaMorphisms                   | 0m03.63s
0m03.42s  | Category/Sum                                 | 0m03.38s
0m03.22s  | ExponentialLaws/Law   N/A                    | 0m01.88s
0m03.18s  | Functor/Product/ProductFunctor               | 0m03.37s
0m02.39s  | Grothendieck/ToSet                           | 0m02.58s
0m02.33s  | Hom                                          | 0m01.86s
0m02.30s  | NaturalTransformation/Isomorphisms           | 0m02.94s
0m02.29s  | Subcategory/Sigma                            | 0m02.26s
0m02.22s  | BoolCategory                                 | 0m02.30s
0m02.02s  | Category/Product                             | 0m01.95s
0m01.84s  | NaturalTransformation/CompositionLaws        | 0m01.77s
0m01.84s  | NaturalTransformation/Equality               | 0m01.85s
0m01.81s  | Functor/Composition/Functorial               | 0m01.24s
0m01.76s  | NaturalTransformation/Duals                  | 0m01.92s
0m01.73s  | FunctorCategory/Morphisms                    | 0m01.79s
0m01.68s  | ExponentialLaws/Law1/Functors                | 0m01.33s
0m01.58s  | NaturalTransformation/Composition/Functorial | 0m01.52s
0m01.50s  | NaturalTransformation/Product                | 0m01.52s
0m01.36s  | NaturalTransformation/Composition            | 0m01.34s
0m01.31s  | Functor/Pointwise                            | 0m01.29s
0m01.15s  | Subcategory/SigmaObjects                     | 0m01.22s
0m00.92s  | Comma/Projection                             | 0m00.81s
0m00.84s  | CategoryOfSections                           | 0m00.86s
0m00.77s  | InitialTerminalCategory                      | 0m00.82s
0m00.69s  | Subcategory/Wide                             | 0m00.68s
0m00.66s  | FunctorCategory/Functorial                   | 0m00.52s
0m00.62s  | ExponentialLaws/Law3/Functors                | 0m00.56s
0m00.56s  | Cat                                          | 0m00.42s
0m00.56s  | Common                                       | 0m00.54s
0m00.54s  | NaturalTransformation/Sum                    | 0m00.48s
0m00.48s  | Functor/CompositionLaws                      | 0m00.47s
0m00.42s  | Cat/Morphisms                                | 0m00.40s
0m00.42s  | IsGroupoid                                   | 0m00.32s
0m00.41s  | IndiscreteCategory                           | 0m00.34s
0m00.38s  | Discrete/Duals                               | 0m00.35s
0m00.35s  | NaturalTransformation/Identity               | 0m00.28s
0m00.31s  | SetCategory                                  | 0m00.22s
0m00.29s  | FunctorCategory                              | 0m00.30s
0m00.28s  | Category/Objects                             | 0m00.22s
0m00.28s  | Functor/Duals                                | 0m00.27s
0m00.25s  | Grothendieck/ToCat                           | 0m00.26s
0m00.24s  | DependentProduct                             | 0m00.22s
0m00.24s  | ExponentialLaws                              | 0m00.22s
0m00.23s  | Functor/Composition                          | 0m00.22s
0m00.21s  | Category/Core                                | 0m00.20s
0m00.20s  | NatCategory                                  | 0m00.21s
0m00.19s  | ExponentialLaws/Law3                         | 0m00.19s
0m00.18s  | ExponentialLaws/Law1                         | 0m00.18s
0m00.18s  | ExponentialLaws/Law2                         | 0m00.18s
0m00.18s  | Adjoint                                      | 0m00.16s
0m00.17s  | Category/Duals                               | 0m00.13s
0m00.17s  | NaturalTransformation/Core                   | 0m00.16s
0m00.17s  | NaturalNumbersObject                         | 0m00.19s
0m00.16s  | Adjoint/Identity                             | 0m00.20s
0m00.16s  | Category/UnivalentCategory                   | 0m00.13s
0m00.16s  | Coq/Arith/Plus                               | 0m00.17s
0m00.16s  | Pseudofunctor                                | 0m00.15s
0m00.16s  | ComputableCat                                | 0m00.16s
0m00.15s  | Coq/Logic/Decidable                          | 0m00.14s
0m00.15s  | NatCategory/Duals                            | 0m00.18s
0m00.14s  | Coq/Arith/Lt                                 | 0m00.10s
0m00.12s  | Category/StrictCategory                      | 0m00.10s
0m00.12s  | Functor                                      | 0m00.11s
0m00.12s  | Utf8                                         | 0m00.11s
0m00.12s  | Functor/Core                                 | 0m00.10s
0m00.12s  | ExponentialLaws/Law4                         | 0m00.12s
0m00.11s  | NaturalTransformation                        | 0m00.10s
0m00.11s  | Grothendieck                                 | 0m00.11s
0m00.11s  | Peano                                        | 0m00.11s
0m00.11s  | DiscreteCategory                             | 0m00.13s
0m00.10s  | Functor/Identity                             | 0m00.11s
0m00.10s  | Coq/Arith/Compare_dec                        | 0m00.14s
0m00.09s  | Coq/Arith/Gt                                 | 0m00.09s
0m00.09s  | Subcategory                                  | 0m00.11s
0m00.08s  | Subcategory/Full                             | 0m00.09s
0m00.08s  | Category                                     | 0m00.09s
0m00.07s  | Coq/Arith/Le                                 | 0m00.08s
0m00.05s  | Notations                                    | 0m00.04s
0m00.05s  | NotationsUtf8                                | 0m00.06s