Include quickcheck-instances in Haskell Platform

[phadej]

quickcheck-instances provides instances for QuickCheck type classes for packages in Haskell Platform. I think it's natural for the package to be in HP itself. We agreed with maintainer of QuickCheck that it will have unconditonal API, which means that some instances even for base types (like NonEmpty) are in quickcheck-instances.

quickcheck-instances provides instances for uuid-types too which is small and handy package, but not in HP at the moment.