Camera pan/tilt/yaw control from Flight Data screen

From tablet devices this feature would be a great one to have. Full control over pan/tilt/yaw of the camera gimbals.

This idea is to perhaps have small circles or virtual gimbal look on the screen where the user swipes or presses to move the virtual gimbal around controlling the camera. This way, total control of a unit setup with FPV can be completely controlled from the computer with no need for a RC transmitter or joystick.

Start at the Mission Planner Flight Data screen and inspect how camera gimbals are currently represented or controlled. Define the tablet interaction for pan, tilt, and yaw, then trace how those controls would reach the unit; done means all three axes can be controlled from the screen without a transmitter or joystick.

Written by the indexing model from the issue text.