[xmonad] xmonad-extras is now on hackage

The xmonad-extras package which contains some additional functionality that requires additional dependencies is now on Hackage: http://hackage.haskell.org/package/xmonad-extras-0.9 It includes a prompt for MPD, volume control and a way to evaluate Haskell expression at runtime, similar to Emacs' eval feature. If anyone has some modules or ideas that can't go in contrib due to dependencies, patches and/or suggestions are always welcome.