RobotecSpectatorCamera: Add proper handling when there is more than one component on the scene

[patrykantosz]

RobotecSpectatorCamera cannot handle now a situation, when more than one of such component is on the scene (e.g. few cars with RobotecSpecatorCamera component) - in such situation controlling the camera is a nightmare (camera jumps, lack of smooth movement etc.). This should be fixed.