Show Audio Time Units to also show FRAMES and optionally move in frame increments

Audio time unit display would be way more useful if it also showed the frame number.
i.e. HH:MM:SS:FF.SAMPLES

e.g. instead of 12:11:16.960 it could show 12:11:16:05.960
- with the frames incrementing every (sample rate / fps) time units. Maybe with the samples a different colour when not on a frame boundary. 

Added bonus -  moving to have frame + multiple frame increments as an option.