Add Option to Disable HLS

[pierfied]

Changes
Adds an option in settings to disable HLS with exoplayer.

Issues
This is a workaround for subtitles getting out of sync when skipping around/resuming certain video files when using HLS
(issue #3492).

[nielsvanvelzen]

The app relies on HLS for all streams when remuxing/transcoding. I'm not strictly opposed to change that but it should be substantiated why another approach is better and properly tested.

I'm not a fan of a preference for it though, that only makes testing harder. We should do everything over HLS or nothing.

[viown]

Subtitles going out of sync should only occur during transcoding (not while direct playing/streaming), so maybe the client can request burn-in when the video has to be transcoded?

[pierfied]

In retrospect, yes, I think trying to burn in subtitles when transcoding is probably a simpler and safer solution. If that would be a preferred route, we can close this PR and open a new one.

[nielsvanvelzen]

Can you try #3825 (or master branch since it's already merged) and let me know if that fixes those sync issues for you?

[pierfied]

From a quick test it looks like it does fix the sync issue! I will go ahead and close this PR.