Remove unnecessary header dependencies.
Trivial test addition.
Use less pointers in transmission loader data.

- Only RobotHW and RobotTransmission instances are pointers as they are owned
  by the robot hardware abstraction. The rest are plain members whose lifetime
  is bound to the loader struct.
Test transmission handle duplication.
Fix license header in some files.
Merge branch 'hydro-devel' into transmission_loader
Fix license header in some files.
Fix compiler warning.
Move from postfix to prefix increment in loops.

Detected by cppcheck 'postfixOperator' warning.
Efficiency fix.

- cppcheck flagged a [passedByValue] warning. Using const references instead.
Fix resource check for multi-dof transmisisons.
Make position joint limits handle opn loop.

- Lowers the entry barrier for simple robots without velocity measurements,
  poor control tracking or with a slow update rate.