[Xmonad] xmonad docs and a xprompt screenshot

Hi, I updated the XMonad documentation, after cleaning up a bit the document generation. You can have a look at it here: http://gorgias.mine.nu/xmonad/ There's also a screen shot of the new prompt available here, featuring xmobar at the top and XMonadPrompt with the default configuration at the bottom, while I'm browsing the completions for the viewN internal commands: http://gorgias.mine.nu/xmonadXPrompt.png All the best, Andrea