HoTT/HoTT — pull request #384 by JasonGross (2014-04-27 05:32:32+00:00)
Title: Miscellaneous category theory lemmas

I've nearly finished defining lax comma categories, but don't think they'll be fast enough to merge anytime soon. In the mean time, these were some small lemmas and tactics that came in handy for lax comma categories, and that I don't want to block on that commit.