Initial import

[barulicm]

Imports relevant packages and documentation to get the repo started.

Details:

• Most code files are minimally modified from the versions in our software repo.
• The game controller bridge and vision bridge packages have been merged into the new ssl_ros_bridge package.
• Utilities from ateam_common have been copied into ssl_ros_bridge. Not worth the hassle for now to avoid maintaining duplicates between the two repos IMO.
• Interface types (messages & services) used by these bridge nodes have been moved to the new ssl_ros_bridge_msgs package.

I've got a short list of improvements that could be made to this code. I'll open issues to track those soon. What we've got here works enough to go ahead and get it in.

[chachmu]

Everything builds on my machine but I didn't check if there were any dependencies that should be installed since I just have them already