Added substring-based account selection to xcap_pres_rules

Ignore-this: 66d70fd04843fc58da7ea040e0615824

darcs-hash:20090521072854-1e3d8-05ec9ed727721f71f3b1c6e5016ea2eb6462151e
Update TODO

darcs-hash:20090523082806-58252-bf638ff777f5b8bbec3b46c2c67551b54565c163