Uniformed TCM, reference system and cmd_vel array order.

In this minor version, the TCM is updated to match BlueRobotics' Blue Rov Heavy configuration, the reference system is updated to match the one mostly used in literature on underwater robotics.

The introduced optocoupler PWM error (less than the expected value by 50us) is taken care in the functions that set the pwms. This version is tested on the full hardware outside of the water, presenting no issues at a first glance.

Ready for water tests

This version is ready for water tests. It has been tested outside of the water, and it works fine. Will need extensive underwater testing.