When downloading new media need a way to define the frame-rate.

[richardssam]

We need a way to pre-populate the yml files for some cases. Perhaps the code can add any missing field, e.g. adding in the frame-range, even if the frame-rate already exists.

See richardssam/ffmpeg-tests#14 for the original source of this ticket.

[apetrynet]

I can add a default/fallback value for the frame rate. Do you have a suggested rate? 24 perhaps?