Feature request: Specify Tempo restrictions

[cviebrock]

I'm not sure if this project is maintained anymore, but a nice feature for building playlists (especially for workouts) would be to limit the tracks to a certain tempo or range of tempos. I know this information is available via Spotify's API (since other tools like playlistmachinery.com use it), so being able to do something like this would be nice:

#similar The Rolling Stones
#tempo 120-140

Thanks!