[FIX] groups: Fix some curious code regarding intertiki where a username with @ in it would get modified even if the "interlist" pref isn't being used. Also actually use the modified group  list set there.
[FIX] groups: Fix some curious code regarding intertiki where a username with @ in it would get modified even if the "interlist" pref isn't being used. Also actually use the modified group  list set there.

git-svn-id: 7564fe402ed407387e083b9f1c8ef2c2bd7bb5d7@56209 b456876b-0849-0410-b77d-98878d47e9d5

oregional/tiki,oregional/tiki,tikiorg/tiki,tikiorg/tiki,tikiorg/tiki,oregional/tiki,tikiorg/tiki,oregional/tiki