OSC time and frame messages

[oneofsomany]

The OSC messages for file frame and time work well but they do not take into account a seek+length. The messages both seem to return the current and total frames or time for the entire file.

Either, they should be showing the total frames that should play (I.E., the SEEK+LENGTH combination)

Or, there should be messages that show frames/time total to play - for purposes of tracking file position (progress bars) and timers for triggering events at specific points in the playback.

[hreinnbeck]

I do this by changing the /file/frame OSC in ffmpeg_producer.cpp to use "frame_number_" and "nb_frames()" (with #239). It also appears to run a lot smoother.