There are a number of applescripts listed in this repository, spotify_control.applescript takes a command:
osascript spotify_control.applescript {command}
{command} can be:
toggleortfor toggle play statenextornfor play next songprevorpfor play previous songstoporsfor stop
actions folder stores a list of individual handy actions.
This works best with adding global short cut key using QuickSilver or Alfred. Enjoy!