TH: GHC 7.7 compatibility

`tySynInstD` now bundles together its two paramters in an `TySynEqn`.
Merge pull request #364 from bgamari/master

TH: GHC 7.7 compatibility
Add fundeps to GIxed'

These fundeps are required for the instances of GIxed
which rely on GIxed' constraints in their context to
satisfy their own fundeps
Generate Ixed instances for tuples 2-9
Placate hlint
Include p in GIxed' fundeps
Merge pull request #365 from sonyandy/gixed-fundeps

Include p in GIxed' fundeps
fix GIxed' for ghc-head
Merge pull request #367 from sonyandy/gixed-fundeps

fix GIxed' for ghc-head
Placate hlint
scripts/stats: remove fudge for Zipper; describe in README.md

∙ Zippers were removed in c9c65096d0b90528af37645828180ce52911f723.
scripts/stats: count operators under src/Control/Lens/ separately
Control.Lens.Combinators: merge into Control.Lens.Lens
Control.Lens.Combinators: repurposed to reëxport Control.Lens sans Operators

∙ Closes #289.
Control.Lens.Operators: update export list using scripts/operators
Add a makeClassy_ lens builder
Merge pull request #368 from jwiegley/master

Add a makeClassy_ lens builder
Added corollaries and consequences of the lens laws.
Merge branch 'master' of github.com:ekmett/lens
Add trying_, a version of trying that omits the precise exception