Changes to ghc

Changes to ghc:
commit e94ed11a09befd8a83e21b68cb3d492a6f7a8986
Author: Richard Eisenberg <eir@cis.upenn.edu>
Date:   Fri Apr 4 00:39:59 2014 -0400

    With AutoDeriveTypeable, derive for promoted constructors, too.

    This addresses #8950. However, the problem isn't completely solved,
    because the Prelude types' Typeable instances are not created by
    AutoDeriveTypeable.