[xmonad] darcs patch: Allow users to choose whether the tabbar should always...

Mon Apr 14 15:11:04 EST 2008 Ivan.Miljenovic@gmail.com * Allow users to choose whether the tabbar should always be visible. This uses the improved data structures/code layout from my second patch, but taking into account suggestions by droundy and sjanssen uses the duplicated-methods found in my first patch so that configs currently using Tabbed don't break.