Various fixes. Fix bug where normalize codecs logic to pick when to transcode was the reverse of what we wanted. Beep and white noise are less loud, which prevent issues with ac3 encoder. Channel Icon Overlay doesn't appear during error screen.
Change docker container to use alpine linux, comes with ffmpeg 4.2+ easier.
Encode commercials to be same video codec as programs when channel icons enabled. Resolution/framerate could still be problematic.
