For testing serial motor control.
A bit more cleanup.
Merge branch 'thrusters/serial' into thrusters/test

Conflicts:
	arduino/onboard_controller/onboard_controller.ino
Merge branch 'master' into thrusters/test
Switched motors to Mega's Serial1.
Merge branch 'cleanup' into thrusters/test

Conflicts:
	arduino/onboard_controller/onboard_controller.ino
Serial port is automatically identified.
Update README.md
Merge branch 'serial' into event

Conflicts:
	arduino/onboard_controller/onboard_controller.ino
	processing/control_station/SerialThread.pde