Refactor the serialization
Initial hack on the voting system
Create the voting API
Promise that the indexes are correctly built when the change notification is fired
Return early if the voted entry is exactly below the current song index
Start with the current playlist so changes to the playlist are propagated immediately
Where did that come from
Don't skip if the song is the same as the voted one
Display the number of votes in the UI
Line-up the text on the playlist entries
Reset the votes when the current song index advances and prevent votes from being set on an entry  that is before the current song index
Reject an invalid vote
Reduce the nesting
Send a response for bas requests or fatal server errors
Send the whole playlist, not only the current index
Implement the vote counting in the access control system
Unregister entries automatically when the vote count reaches zero
Register the correct entry

Previously we worked with the previous index, but the entry could have
been moved
Send the remaining votes to the client
Assert that the client has enough votes left