update doc with the current behavior
update doc with the current behavior

CanalTP/navitia,Tisseo/navitia,Tisseo/navitia,xlqian/navitia,CanalTP/navitia,CanalTP/navitia,xlqian/navitia,kinnou02/navitia,Tisseo/navitia,CanalTP/navitia,CanalTP/navitia,xlqian/navitia,Tisseo/navitia,xlqian/navitia,xlqian/navitia,kinnou02/navitia,kinnou02/navitia,Tisseo/navitia,kinnou02/navitia