[Xmonad] darcs patch: make Circle work with Layout class. (and 2 more)

Hi, I started playing with the new class stuff: exciting I'd say. A couple of patches: one to Circle that must export the type constructor. The second one makes TwoPane work with the class system. Just a translation from the old one. I'm trying to grasp the more difficult details ... still have to figure out how to rewrite LayoutHelpers...-;) Andrea Fri Sep 21 23:55:25 CEST 2007 David Roundy * make Circle work with Layout class. Sat Sep 22 14:41:26 CEST 2007 Andrea Rossato * Circle: must export type constructor Sat Sep 22 14:42:10 CEST 2007 Andrea Rossato * make TwoPane work with Layout class