fix: Support for notification queue

docs/control/5-notifications-and-tts.md

@@ -15,6 +15,7 @@ Notification are automatically managed by the application. It will return playba
 ## Play a mp3
 
 To play a short music file as a notification send the following payload to command topic.
+You can send multiple notifications after each other, and they will be played after each other.
 
 Topic: `sonos/uuid_of_speaker/control`
 
@@ -33,6 +34,28 @@ Payload:
 }
 ```
 
+### Experimental notification queue
+
+There is a second implementation of the notification queue, that you can use with the following command.
+You should not mix them, but you we are curious to what you [think](https://github.com/svrooij/node-sonos-ts/issues/119)
+
+Topic: `sonos/uuid_of_speaker/control`
+
+Payload:
+
+```json
+{
+ "command": "notifytwo",
+ "input": {
+ "trackUri": "https://cdn.smartersoft-group.com/various/pull-bell-short.mp3",
+ "onlyWhenPlaying": false,
+ "timeout": 10,
+ "volume": 8,
+ "delayMs": 700
+ }
+}
+```
+
 ### Play notification on all speakers
 
 You can also have a notification play on all groups (all devices that coordinate themself), just send the following message to `sonos/cmd/notify`.
@@ -90,6 +113,11 @@ Have a speaker speak by sending the following to `sonos/uuid_of_speaker/control`
 }
 ```
 
+### Experimental tts queue
+
+There is a second implementation of the notification queue (used by TTS), just change `speak` to `speaktwo` in the above command.
+You should not mix them, but you we are curious to what you [think](https://github.com/svrooij/node-sonos-ts/issues/119)
+
 ### Text to speech on all speakers
 
 Send this payload to `sonos/cmd/speak` to play it on all groups. Same parameters as above.