This functionality has been embedded into the Apple Music application itself: when you press a song (while already playing another song), you get a menu:
Play Now — interrupt what you are playing, and play the item right now
Play Next — put the item right after the current one on your upcoming queue
Play Last — put the item at the end of your upcoming queue (after others)
After your upcoming queue is done playing, you will be returned to the songlist you were previously playing. The upcoming queue is exposed as a normal iPod playlist called Cyueue. This playlist is reset each time you start a new play session with Cyueue.
You can purchase Cyueue from the Cydia Store for $2.49.