Add a docstring to 'setup' and 'teardown'
Add a docstring to 'setup' and 'teardown'

Inform that 'setup' and 'teardown' are for internally use only.

adamcik/mopidy,jodal/mopidy,jcass77/mopidy,adamcik/mopidy,mopidy/mopidy,mopidy/mopidy,kingosticks/mopidy,jcass77/mopidy,jcass77/mopidy,kingosticks/mopidy,kingosticks/mopidy,jodal/mopidy,mopidy/mopidy,adamcik/mopidy,jodal/mopidy