Autoupdate documentation with coqdoc to df5dd91

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commit df5dd91944f7fb604bb1f7d390e4c60ad81b182f
Author: Jason Gross <jgross@mit.edu>
Date:   Fri Sep 13 14:42:18 2013 -0400

    Anomaly: Uncaught exception Invalid_argument("to_constraints: non-trivial algebraic constraint between universes", _).