Added a topic that shows program data for any program

[dzoberti]

This can be useful for a number of reasons. Mainly it allows to detect when the robot has finished executing a script received on the script_command topic

[fmauch]

Thank you very much for your contribution. However, please be aware that this is already part of #35 if I understand this correctly. If that is the case, we will probably not merge this, but it can serve other users as a good base to achieve the same until #35 is finished.

[github-actions[bot]]

This PR hasn't made any progress for quite some time and will be closed soon. Please comment if it is still relevant.