Use true pitch/yaw/roll rotations without loss of precision by pgimeno (#8019)

Use true pitch/yaw/roll rotations without loss of precision by pgimeno (#8019)

Store the rotation in the node as a 4x4 transformation matrix internally (through IDummyTransformationSceneNode), which allows more manipulations without losing precision or having gimbal lock issues.

Network rotation is still transmitted as Eulers, though, not as matrix. But it will stay this way in 5.0.