Spotify token refresh - feature request

[ammonhaggerty]

The Spotify provider succeeds in providing a login token, but is missing an important step to be useful for any API access. If you look at the Spotify Authorization Code Flow diagram (https://developer.spotify.com/documentation/web-api/tutorials/code-flow), after the successful login, a second "token refresh" is required to get valid tokens (step #2). Also, the valid tokens expire in 1 hour, so having the ability to refresh tokens as a part of the Socializer plugin would be very helpful. Thank you!