Obstacle Avoidance and Avoidance Override Node

[DrCurry]

Convert last years code into ROS compatible code

[EpicWolverine]

This node is using the ROS-ified code of the old obstacle detection code (which hasn't been converted yet). That'll do the detection work, and then the same node will forward data about where the obstacles are to mapping/path planning. It will also monitor to see if an obstacle is too close (this distance will be configuable via a rosparam) and if it is, it will send a twist message to auto control logic (which will prioritize messages from that topic) that stops the robot.