X.A.GroupNavigation with containers < 0.3.0.0 compatibility
X.A.GroupNavigation with containers < 0.3.0.0 compatibility

Ignore-this: e0cf2a784ff02829ad10962863fd50ed

This patch replaces the use of Seq.filter and Seq.breakl with two
functions flt and brkl that do the same.  This is necessary to
keep compatibility with containers < 0.3.0.0 because Seq.filter and
Seq.breakl were introduced only in containers 0.3.0.0.

darcs-hash:20100514222153-18a2b-0b11f7214f473df160de9db0e6dfc9ff0ec13376

kmels/xmonad-launcher,kmels/xmonad-launcher