[Yhc] Data.Map

I sent a patch to yhc@haskell.org, but triggered the moderation system for the message being too long. The patch can be found by pulling from my alternate repo at http://www.downstairspeople.org/darcs/yhc_clanehin Note that this repo is inconsistent with what it was yesterday, if you pulled from that, as though by unrecord. So pull freshly if needed. Please advise as needed. --Lane