Include information about frame limits and estimated number of frames/cadence when creating a movie

[Keith Hughitt]

In order to give users a better feel for how many frames/what frame-rate they can expect when making a movie, provide them with information about the estimated number of frames, current frame limit (based on queue size) and average cadence for the layers they are including.

Perhaps the information can go in an "advanced" section during the movie creation process, under a sub-heading "duration and frame rate" or "frame rate and limit"