AOS <-> ROS bridge

[AustinSchuh]

From @jkuszmaul

Create some sort of bridge to allow bridging ROS nodes to AOS, to accommodate people who want to be able to experiment with both.

Exactly how this will look is not entirely clear, but the goal should be to be relatively easy to get working, rather than focusing on getting every single possible feature working.

[jinchenglee]

As a first and probably least intrusive step, maybe a ROS message monitor node to attach to AOS? It is read-only and a good way to bridge the protocols.

[AustinSchuh]

Yea, that feels like a decent starting point, and maybe enough. At a minimum, it would trigger feedback on usability, which is also valuable for figuring out what the requirements are.