Integrating the map annotation tool in mas_navigation

[argenos]

This tool was super useful for the athome team during German Open this year. I' created https://github.com/b-it-bots/mas_navigation/issues/12 to document the integration or the creation of a similar tool if the original authors are not interested in integrating this there.

In addition, I have a few minor issues/suggestions:

1. Currently the tool looks for the mcr_default_env_config package and writes it to the map specified in ROBOT_ENV. athome doesn't save the maps there, and using the environment variable becomes a bit problematic to configure when annotating different maps.
   Possible solution:
   • configure this from within rviz (once the plugin has been launched)
   • explore the use of parameters or topics
2. Writing the poses directly on the robot
   Possible solutions:
   • Doing this via topics with a node

If the original authors don't want to take care of the two last solutions, it's alright! I'll be happy just to get this starting code over there.

[argenos]

I've opened a PR in mas_navigation_tools: b-it-bots/mas_navigation_tools#2