add stand alone features from VadereManagement module:

• single step mode in GUI: Allows the user to step through the simulation one step at a time to identify bugs.
• simplify obstacles: Merge multiple obstacles based on the convex hull their points create. The merge can be undon
• add features to open street map (osm) importer:
  1. import 'open' paths as polygons with a specified width. With this it is possible to create walls or subway entrance
  2. add option to include osm ids into each obstacle