Changelog for gray-code-0.3.1

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0.3.1: revert API to be backwards compatible with 0.2.2, requires GHC >= 7.8 0.3: DON'T USE THIS VERSION. rely on total functions on FiniteBits, requires GHC >= 7.8 0.2.2: build on GHC 7.6, integrate tests with cabal build 0.2.1: toList' function 0.2: split C.B.G.Bits and C.B.G.List APIs 0.1: initial Hackage release