Add Spotify controls for yourself

Instead of showing those buttons saying you can't play yourself (yuck):

It would be nice to have buttons to pause and skip songs.

Spotify has the following entry points for the API:
Pause - https://api.spotify.com/v1/me/player/pause
Previous - https://api.spotify.com/v1/me/player/previous
Next - https://api.spotify.com/v1/me/player/next

The reference is on https://developer.spotify.com/documentation/web-api/reference-beta/
(It is a beta feature, aparently).