/**
  * Determine if an Organization has room for more Users in it.  A negative
  * org_max_users indicates that it can hold unlimited Users.
  *
  * @return boolean
  */
 public function is_full()
 {
     if ($this->org_max_users < 0) {
         return false;
         // < 0 == no user limit
     }
     $n = UserOrg::get_user_count($this->org_id);
     return $n >= $this->org_max_users;
 }