Re CLC #300 - Specify fmap for NonEmpty as map

See:
* https://github.com/haskell/core-libraries-committee/issues/300

Seeks to:
* move existing instances for NonEmpty (except of Eq and Ord) out of GHC.Internal.Base into new GHC.Internal.Data.NonEmpty (to avoid otherwise unavoidable cycles in the module graph);
* move map out of Data.List.NonEmpty (base package) into GHC.Internal.Data.NonEmpty;
* define fmap as map for NonEmpty instance of Functor, avoiding code duplication;
* re-export map from existing GHC.Internal.Data.List.NonEmpty; and
* re-export map from Data.List.NonEmpty (base package);

without breaking anything in the GHC repository.

Various tests *.stdout and *.stderr files are amended also.