Changes to ghc

Changes to ghc:
commit e55acf007f5109b42a2e388eaca63445bbbc7376
Author: Herbert Valerio Riedel <hvr@gnu.org>
Date:   Thu Mar 13 22:09:56 2014 +0100

    Update to containers-0.5.5.0

    This adds role annotations to Map and Set and therefore addresses #8718

    Signed-off-by: Herbert Valerio Riedel <hvr@gnu.org>