Autoupdate documentation with coqdoc to 663ef61

Generated with `make html` on commit:

commit 663ef61bad84f386b11898afb878e1ec617ec770
Merge: 458c3a6 36573c5
Author: Bas Spitters <b.a.w.spitters@gmail.com>
Date:   Mon Aug 26 12:02:17 2013 -0700

    Merge pull request #199 from andrejbauer/master

    Update CREDITS.txt

commit 36573c51ce3a6acd7d3eeb9965d15375982be1e7
Author: Andrej Bauer <Andrej.Bauer@andrej.com>
Date:   Mon Aug 26 17:56:44 2013 +0200

    Update CREDITS.txt