record: add extension property to source
record: add extension property to source

nemomobile/pulseaudio-module-cmtspeech-n9xx,maemo-foss/maemo-multimedia-pulseaudio-modules-meego,jusa/pulseaudio-modules-nemo,maemo-foss/maemo-multimedia-pulseaudio-modules-meego,jusa/pulseaudio-modules-nemo,maemo-foss/maemo-multimedia-pulseaudio-modules-meego,jusa/pulseaudio-modules-nemo,nemomobile/pulseaudio-module-cmtspeech-n9xx