Correction of velocity collision filter

From hydro there is change in [costmap_2d node](http://wiki.ros.org/costmap_2d) so that otuput is [OccupancyGrid](http://docs.ros.org/hydro/api/nav_msgs/html/msg/OccupancyGrid.html) instead of [GridCell](http://docs.ros.org/hydro/api/nav_msgs/html/msg/GridCells.html).