exo: Add initial recipe with version 0.6.2

* python bindings removed here (will be moved to pyxfce mainline [1])
* TBD: gnomemount replacement on postinst [2]

[1] http://comments.gmane.org/gmane.comp.desktop.xfce.devel.version4/19560
[2] http://wiki.xfce.org/gnomemount-replacement