Autoupdate documentation with coqdoc to 6fd5af4

Generated with `make html` on commit:

commit 6fd5af42ee545b13c22a8f9bc291d0038b735de8
Author: Jason Gross <jgross@mit.edu>
Date:   Wed Sep 25 13:34:11 2013 -0400

    Functor.ProductFunctor -> Functor.Product.ProductFunctor