~/.xinitrc: Fullscreen-friendly taffybar.

Somehow when started manually (i.e. after xmonad) it's actually on top
of it, which is not what I want. So I'll just start it before xmonad
itself and all is well.

I still wonder whether this is normal behaviour.
~/.xmonad: Toggle fullscreen (docklessness) w/ M-f.

Nice, one thing that I missed from awesomewm.