Added node that fakes missing topics in MORSE, e.g. /motor_state

Added a simple node (scitos_node) that publishes topics and provides services according to the real robot.

This node runs in parallel to morse and thereby complements it by providing missing topics such as /motor_state.
As this node should be launched whenever the scitos robot is used in MORSE, I added a launch file called scitos.launch, which now bundles the scitos robot state publisher and the scitos_node. I included this new launch file in all existing simulations (bham,tum,uol). That is, future changes wrt to the robot should be realized within scitos.launch instead of the individual environment launch files.