[Feature] inject notification node

With the new notification center, we are able to inject notifications.

Inject  `msg.payload` should be something like:
```
{
  "type": 0,
  "title": "Hello world",
  "message": "Node-RED on Victron Energy devices is cool!"
}
```

Which then translates to a `SetValue` `"${type}\t${title}\t${message}"` on `com.victronenergy.platform` `/Notifications/Inject`

So this will need its own control node. 