ikiwiki/ todo/ allow wiki syntax in commit messages

Commit messages should allow wiki syntax, and RecentChanges should format them accordingly.

--JoshTriplett

That's a neat idea! It would probably have to be only the simpler bits, without preprocessor directives -- wouldn't want a commit message inlining a whole page into RecentChanges. Of course, it could only use one of the available markups, ie the default markdown. --Joey

To go along with this, the preview should show the formatted commit message. --JoshTriplett