[dwm] [patch] Taskbar

Hi,

I attach a little patch (6 extra sloc) which implements a "taskbar" for
dwm, it fits quite well to my needs when using monocle, floating... due
to you can always see the titles of all clients in the current view.

Take care of ClkWinTitle is not "subdivided" to provide mouse actions
over each client title.

It might be useful for someone else :)

Kind regards,
Nibble