Design concept for mode management

[elfutzi]

• figure out which modes must be available in a fist step, e.g. forward, backward, stop, autonomous drive, teleoperation, etc.
• figure out which dependencies to other nodes (existing and planned ROS nodes) exist / will exist
• figure out which input signals are needed to switch between modes
• figure out which output signals are needed to inform other nodes about mode changes
• write a ticket for implementation with elaborated concept