First attempt at automatic PID calibration.
Enabled motor encoders.
Going on with PID calibration.
Fuck automatic calibration, let's do it by hand.
Use external encoders for position.

By default position_manager computes the position using the motor encoder when
both are enabled. Force it to use external encoders.
Added "position_set" lua binding.
forgot a return
Go forward only.
PID are tuned.
Added a custom makefile.

17x times faster than Altera !!!