Camera control for rotorcraft. The camera is controled by the heading of the vehicle for pan and can be controlled by a servo for tilt if defined. Four modes: - NONE: no control - MANUAL: the servo position is set with PWM - HEADING: the servo position and the heading of the rotorcraft are set with angles - WP: the camera is tracking a waypoint (Default: CAM) If ROTORCRAFT_CAM_SWITCH_GPIO is defined, this gpio is set/cleared to switch the power of the camera on in normal modes and disable it when in NONE mode. On boards with CAM_SWITCH, ROTORCRAFT_CAM_SWITCH_GPIO can be defined to CAM_SWITCH_GPIO.