Get user_id from a notification template.

@@ -425,6 +425,7 @@ function send_triggered_notification($uid = 0, $trigger = 'NO_TRIGGER', $args =
                 'email_address_preference',
                 'email_address_preference',
                 'preferred_email',
                 'preferred_email',
                 'member_id',
                 'member_id',
+                'user_id',
                 'course_note_listing'
                 'course_note_listing'
             ];
             ];