Enable instant listening and disable confirmation sound

buildroot-external/rootfs-overlay/etc/mycroft/mycroft.conf

@@ -1,4 +1,5 @@
 {
+  "confirm_listening": false,
   "play_wav_cmdline": "paplay %1",
   "play_mp3_cmdline": "mpg123 %1",
   "ipc_path": "/dev/shm/mycroft/ipc/",
@@ -8,7 +9,8 @@
   },
   "disable_xdg": false,
   "listener": {
-    "mute_during_output": false
+    "mute_during_output": false,
+    "instant_listen": true
   },
   "hotwords": {
     "hey mycroft": {