added start_listening.wav to mycroft-base-MANIFEST.in
added start_listening.wav to mycroft-base-MANIFEST.in

linuxipho/mycroft-core,Dark5ide/mycroft-core,forslund/mycroft-core,MycroftAI/mycroft-core,aatchison/mycroft-core,aatchison/mycroft-core,forslund/mycroft-core,MycroftAI/mycroft-core,linuxipho/mycroft-core,Dark5ide/mycroft-core