Feature/dynamic configs

[Schmluk]

• Initial implementation of dynamic configs and dynamic config servers.
• Also adds a ROS server to set configs via topics (not via params for now, although we could think of this too)
• Add utests
• Add demo with two GUIs to set configs (Plain YAML and specialized fields, although experimental)
• Add docs
• Minor refactor and cleanup of settings. This will be breaking interfaces though (should be easy to fix if used)