Added camera calibration + py script to undistort images

As well as 2 distorted/undistorted examples
Source.{update->position}
Made the call server non-blocking

THe main loop runs at MAIN_LOOP_FPS (currently 60FPS)

Also: introduced a stepping time when calling table.step (not used yet)
Isolate Color + add Color.interpolate
Introduce 'PLAIN' mode + fading between colors