Autoupdate documentation with coqdoc to fb45001

Generated with `make html` on commit:

commit fb4500162a432b6c7d402eb4c0926a600cac75b4
Author: Jason Gross <jgross@mit.edu>
Date:   Wed Oct 2 05:55:28 2013 -0400

    Remove prod_eta

    It already exists in HoTT as eta_prod.