Is there a way to implement a feature in which the camera will be automatically fixed (pointed) to one GPS point, and, during the flight the gimball angle and quad orientation be adjusted automatically no matter where the quad is moving?

You can get DJI ground station and have that feature.
The new DJI Phantom 3 has that capability and you can have it fly to a waypoint and while its headed there you can turn the Phantom any direction you want and it will still fly to your waypoint.