[modules/pulseaudio] Start pulseaudio daemon, if not running
[modules/pulseaudio] Start pulseaudio daemon, if not running

Since the module requires the pulseaudio daemon to be running, in order
to query system information such as the default source/sink and the
current volume, start the daemon, if necessary.

fixes #108

tobi-wan-kenobi/bumblebee-status,tobi-wan-kenobi/bumblebee-status