Video details: «Part of series» should be shown

[dagraf]

Currently, the "Video details" section does not state which series this video is part of. This information should be included. I suggest listing it above or below 'Referencing pages'. Of course, it would also be great if it would be possible to change which Series this video is part of.

Note: The same should be true for 'Part of playlist'.

[LukasKalbertodt]

Yup, we want to make the series editable here. Note that a video can be included in multiple playlists, so that would be a list (and not editable from the event page). But I think all of that is part of #1392