Fixed minor issue with cables daemon initialization
In order to remove stale rqueue/*.new directories, cabled init service
invokes "/usr/libexec/cable/cabled init" via sudo. However, due to a bug
in sudo, the full group vector is not set:
http://www.gratisoft.us/bugzilla/show_bug.cgi?id=516
This prevented cabled from having access to the relevant directories.
The issue is now fixed by explicitly specifying the legion group.