update README

Signed-off-by: Maxime CLEMENT <[email protected]>

planning/motion_velocity_planner/autoware_motion_velocity_out_of_lane_module/README.md

@@ -91,6 +91,8 @@ Whether it is decided to slow down or stop is determined by the distance between
 If this distance is bellow the `actions.slowdown.threshold`, a velocity of `actions.slowdown.velocity` will be used.
 If the distance is bellow the `actions.stop.threshold`, a velocity of `0`m/s will be used.
 
+In addition, if parameter `action.use_map_stop_lines` is set to `true`, then the stop point may be moved to a stop line preceding the stop point where ego can confortably stop. Stop lines are defined in the vector map and must be attached to one of the lanelet followed by the ego trajectory.
+
 ![avoid_collision](./docs/ttcs_avoid.png)
 
 ### About stability of the stop/slowdown pose
@@ -126,6 +128,7 @@ Otherwise, the stop or slowdown pose will only be discarded after no out of lane
 
 | Parameter /action              | Type   | Description                                                           |
 | ------------------------------ | ------ | --------------------------------------------------------------------- |
+| `use_map_stop_lines`           | bool   | [-] if true, try to stop at stop lines defined in the vector map      |
 | `precision`                    | double | [m] precision when inserting a stop pose in the trajectory            |
 | `longitudinal_distance_buffer` | double | [m] safety distance buffer to keep in front of the ego vehicle        |
 | `lateral_distance_buffer`      | double | [m] safety distance buffer to keep on the side of the ego vehicle     |