Changes to ghc(2)

Changes to ghc:
commit 8d34ae393eb49121e51bf1f01d575928aece5cfe
Author: Joachim Breitner <mail@joachim-breitner.de>
Date:   Thu Jan 23 15:13:30 2014 +0000

    Some polishing of the demand analyser.

    I did some refactoring of the demand analyser, because I was smelling
    some minor code smell. Most of my changes I had to undo, though,
    adding notes and testcases on why the existing code was correct after
    all.

    Especially the semantics of the DmdResult is confusing, as it differs in
    a DmdType and a StrictSig.

    I got to imrpove the readability of the code for lubDmdType, though.

    Also, dmdAnalRhs was a bit fishy in how it removed the demand on
    further arguments of the body, but used the DmdResult. This would be
    wrong if a body would return a demand type of "<L>m" (which currently
    does not happen).  This is now treated better in removeDmdTyArgs.

commit 26acb4981d02eb59c72d059cb196c04a7ac945af
Author: Joachim Breitner <mail@joachim-breitner.de>
Date:   Thu Jan 23 16:40:10 2014 +0000

    More demand analyser test cases

    catching mistakes that I had during my refactoring, and which I do not
    want to do again.