Added System (= systemsound) playback class.
Added System (= systemsound) playback class.

maemo-foss/maemo-multimedia-ohm-plugins-misc,jusa/ohm-plugins-misc,tswindell/ohm-plugins-misc,tswindell/ohm-plugins-misc,jusa/ohm-plugins-misc,jusa/ohm-plugins-misc,jusa/ohm-plugins-misc,maemo-foss/maemo-multimedia-ohm-plugins-misc,tswindell/ohm-plugins-misc,maemo-foss/maemo-multimedia-ohm-plugins-misc