LJ::send_comm_invite — Sends an invitation to a user to join a community with the passed abilities.
LJ::send_comm_invite(uuserid, cuserid, muserid, attrs
uuserid. a userid or u object of the user to invite.
cuserid. a userid or u object of the community to invite the user to.
muserid. a userid or u object of the maintainer doing the inviting.
attrs. a hashref of abilities this user should have (e.g. member, post, unmoderated, ...)