Add ability to change rotor angles, aileron angles of TiltrotorPawn in code

[sethmnielsen]

Here is the current architecture:

To pass the rotor values to FlyingPawn, a MultirotorPawnEvents::ActuatorsSignal containing a vector of MultirotorPawnEvents::RotorInfo objects is emitted in MultirotorPawnSimApi::updateRendering(); that signal gets caught by the function AFlyingPawn::setRotorSpeed(), which is where the rotation values for the props of the multirotor mesh are set. The only parameter to setRotorSpeed() is a vector of RotorInfo (speed, direction, thrust, control signal) objects.

Tasks:

• [x] make new container, e.g. TiltrotorInfo holding rotor tilt and aileron states
• [x] new function for setRotorSpeed() that accepts new container
  • [x] code to set prop rotation, engine pitch, and aileron angles
• [x] make new ActuatorsSignal - a typedef for common_utils::Signal<const std::vector<RotorInfo>&> - that holds new container

[sethmnielsen]

The default params (like rotor poses) for the Tiltrotor are currently hard-coded in TiltrotorSimpleParams.hpp, which calls initializeRotorQuadX() defined in TiltrotorParams.hpp. I think these are the two files that will need to be modified with values for the aircraft in vtol-sim.

[sethmnielsen]

Finished in #9.