SwrContext -> AudioResampler; steals resample method
Adapt decoding example into base of fifo example
Planes pull from extended_data

This is required for higher-channel data. Video
doesn't care.
Fix manual AudioFrame construction
The FIFO example works and plays
Deal with missing channel_layout on streams
Test the fifo!
Notes
Check AudioLayout channel bounds
Resampler mostly works
AudioFormat.container_name
Remove some prints; example uses packed format
Fifo example can play multiple channels
Merge branch 'resample' into develop