Implement steering for the new motors.

[jopgen]

With the new design we are going to be doing regular steering (Not sure what the technical term is?) rather than skid steering. To facilitate this we will need:

• A new modal in the ROS simulation, we don't have too many specifics from Meche right now, but right now just having a basic body with 6 wheels should suffice
• New code for the proper steering