Changes to ghc

Changes to ghc:
commit f8b25c30fe593a1195a4f4840b8773595dd0f2e0
Author: Richard Eisenberg <eir@cis.upenn.edu>
Date:   Fri Nov 22 17:27:32 2013 -0500

    Update to core-spec documentation.

    This update includes some wibbles to make Co_TyConAppCo clearer,
    as well as the introduction of forms for AxiomRuleCo.