Add a "Queue track", or "Play Next" feature

Hello,

I use the "Queue track" feature a lot on players like Clementine. It allows choosing which tracks to play next and in which order, without reordering the playlist. When the queue is empty, back to random or whatever algorithm is chosen to pick the next song.

I badly miss this feature when it is not available. Clementine has a convenient, dedicated UI to manage this queue but I don't use it very often and the feature is still very useful without it.

It would be nice to be able to queue tracks on VLC, especially on Android since this is where I'm using VLC, but it would be great on the desktop version too.

What would need to be done in the VLC codebase to support such a feature?

ps: sorry if this has already been reported, I could not find anything on the bug tracker about that.