[Xmonad] Freeze for 0.4

We're planning to release 0.4 over this weekend. In preparation for the release xmonad, XMonadContrib and X11-extras are under a feature freeze. Feel free to send bug fix and documentation patches, but please keep new feature patches to yourself until after the release. If there are any important issues that should be addressed before 0.4, now is the time to speak up! Cheers, Spencer Janssen