feat/drop_ww_sounds_from_STT_audio

[JarbasAl]

          if we want to know when sound stops playing

    def _play_sound(self, uri: str, timeout=0.5, message: Optional[Message] = None):
        message = message or Message("", context={
            'client_name': 'ovos_dinkum_listener', 'source': 'listener',
            'destination': ["audio"]  # default native-source
        })
        self.bus.emit(message.forward("mycroft.audio.play_sound", {"uri": uri}))
        # block waiting for ovos-audio to report sound finished playing
        if not self.config.get("instant_listen", True):
            sess = SessionManager.get(message)
            SessionManager.wait_while_speaking(timeout=timeout, session=sess)

we could use this to to know how much time (and therefore chunks) to drop from beginning of STT audio

but i would put this into it's own flag and do it in a separated PR

Originally posted by @JarbasAl in #125 (comment)