First stable release of `spotctl`

This is the first stable release of spotctl 🎉. Currently spotctl allows you to:

$ spotctl -h
A command-line interface to Spotify.

Usage:
  spotctl [command]

Available Commands:
  help        Help about any command
  login       Login with your Spotify credentials
  logout      Clear your local Spotify credentials
  next        Skip to the next track
  pause       Pause Spotify playback
  play        Resume playback or play a track, album, artist or playlist by name
  player      Show the live player panel
  prev        Return to the previous track
  repeat      Toggle repeat playback mode
  shuffle     Toggle shuffle playback mode
  status      Show the current player status
  version     Show version.
  vol         Set or return volume percentage

Flags:
  -h, --help   help for spotctl

Use "spotctl [command] --help" for more information about a command.

See a demo here:

Enjoy and Merry Christmas🎄 !