Add RobotUnitModules::ControllerManagement::deactivateAndDeleteNJointController (and memberversions for NJointController)

Add versions of {delete,[de]activate}NJointController[s] taking pointers and change code to use them

Also fix some errors due to value return instead of reference return

Refactored the whole RobotUnit (split it in modules, cleaned up code, added doxygen, removed undefined behavior, reduced data sharing)

Code cleanup

See merge request ArmarX/RobotAPI!37