Add a "playlist from playlist" option

[Polochon-street]

note to self: merge the queue_from_song and queue_from_current_playlist together? Pros: simplifies stuff Cons: A lot of different cases to treat:

• Queue songs similar to the current queue (preserve the current queue, no other choice anyways)
• Queue songs similar to the current song, preserve the current queue
• Queue songs similar to the current song, after having removed the current queue save for that song
• Queue songs similar to the song specified on the CLI, preserve the current queue
• Queue songs similar to the song specified on the CLI, remove the current queue