[dwm] [patch] bar autohide

this patch (which works with yesterday hg tip, dunno if there have
been any changes) is an autohide mode for the tag bar.
i had always hated autohiding bars, but the other day reading
http://www.asktog.com/columns/022DesignedToGiveFitts.html and after
some experimentation with bwm i decided to try it showing the bar when
you go to the upper left corner.
the patch also adds some new functions with the mouse (when 4.4 is
relased, i will update the patch with the diff of the man page to
document these changes):
Button 2: zoom
MouseWheel: focus prev/next client
ModKey+Button1 in the arrangement symbol: toggle floating
the only problem i have found is that the autohidden bar is always at
the top, if somebody wants to use this patch with the bar at the
bottom drop me a line.

ps: im still trying new ideas with bwm, 0.2 will probably be relased
the next week, thanks to anselm for his advice (im reimplementing
everything with XReparentWindow as you told me, rio sources in
plan9ports is being very helpful)

-- 
- yiyus || JGL .