Enter unlinking mode for a group

def enter_unlink_mode(self):
        """Enter unlinking mode for a group"""
        self.logger.info("enter_unlink_mode Group %s", self.group_id)
        self.scene_command('0A')
        # should send http://0.0.0.0/0?0A01=I=0

        ## TODO check return status
        status = self.hub.get_buffer_status()
        return status