1. Extract "bare ODL" and run it.
2. feature:install odl-restconf
3. feature:install odl-clustering-test-app
4. feature:install odl-netconf-connector-all
5. Configure a websocket of scope "BASE" or "ONE" on "/cars:car"
6. Run the websocket listener on a terminal, listening on the websocket, asking
it to expect at least 2 messages.
7. Create a car
8. You will see a message to pop up on the websocket listener's terminal,
containing data from your car.
9. Create another car
10. No messages on the websocket listener terminal.

In step 6 post this to create the notification stream:

{
"input":

}

In the step 10 another message shall be seen with data from the other car
instead of the listener being silent.

The same happens when you delete the car you just created in step 9.

When you stop the websocket listener on that terminal, restart the ODL and
then do steps 5 to 7 again, you won't see any more messages on that terminal.

If you do the steps in the order 1-4,7,5,6,delete the car created in step 7
(i.e. you create the car before the notification is created) then you won't
get any notifications from the websocket.

The correct behavior is to receive notifications for every "create" and
"delete" executed on that list.