Support watching deletes

- https://github.com/esbtools/lightblue-notification-hook/blob/master/lib/src/main/java/org/esbtools/lightbluenotificationhook/NotificationHook.java#L175
- https://github.com/esbtools/lightblue-notification-hook/blob/master/lib/src/main/java/org/esbtools/lightbluenotificationhook/NotificationHook.java#L308