Better user output, kinematic solver error handling, disclaimer

Many changes:

- Improved documentation (XBox buttons, launch file, etc)
- Add JSK disclaimer to python script
- Improved user output to help debug various possible problems
- Changed outputted topic name to just end effector name when end effector changed
- Added ability to give up on a planning group if it does not initialize, and try a different one. If a planning group has missing or misconfigured kinematics solvers, it will never resolve with this script (until now)