resolves #1880

Had to update the script now we use weblate

Before applying this commit, check you don't have duplicates local
actors in your database:

select "preferredUsername" from actor where "serverId" is null group by "preferredUsername" having count(*) > 0

If you have some results, it seems you have duplicate channels/accounts.
For every entry, you'll have to change the preferredUsername of the
entry you want (so they are unique). The updated actors could have some
federations issues. Sorry.

This patch adds an audio-only option to PeerTube by means of a new transcoding configuration which creates mp4 files which only contain an audio stream. This new transcoder has a resolution of '0' and is presented in the preferences and in the player resolution menu as 'Audio-only' (localised). When playing such streams the player shows the file thumbnail as background and disables controls autohide.

Audio-only files can be shared and streamed just like any other file. They can be downloaded as well, the resulting file will be an mp4 container with a single audio stream.

This patch is a proof of concept to show the feasibility of 'true' audio-only support. There are better ways of doing this which also enable multiple audio streams for a given video stream (e.g. DASH) but as this would entail a fundamental change in the way PeerTube works it is a bridge too far for a simple proof of concept.

In favour of HLS

That don't have a shared inbox, or a URL

* Start working on autoplay of next video

* Ignore changes made by gitpod

* Apply changes from PR#1370

* Correct the spelling of recommendations

* Fix linting errors

* Move boolean check to existing onEnded handler

* Pick a random video until the recommendations are improved

* Add simple tests for autoPlayNextVideo

* Fix lint

...again