We were not (and probably wont be ) using any worthwhile `requests`
features (beside `raise_for_status()`) and the `timeout` session
parameter propagation vs adapter plugging "thing" in requests just
annoys me deeply (not that kind of "... Human (TM)")
Remove dependency to `webvtt-py` which was both too much and not enough
for our use case.
Implement a basic WebVTT to SRT converter according to ArteTV's usage of
WebVTT features.
- versions => renditions
- resolutions => variants
- ranges and/or chunks => segments
- version index => master playlist
- other index => media playlist url
For now, the CLI has not been updated with this terminology, only the
code.
* video resolution selection
* use video/audio URLs directly in FFMPEG command
(no temporary m3u8 file anymore)
* embed subtitle in final video file
* moved to MKV container to enable auto-on subtitle
