Report tree topology to root (AEGHB-222)

[redfast00]

This PR will add support to get the topology of the mesh network

• [X] Child nodes send connected clients to root
• [ ] Root parses the JSON messages and sends events
• [ ] Root sends events for its own clients
• [ ] Test the setup

Note that the code is not ready to be committed yet, there are test prints all over the place, this draft PR is only to show the direction I'm going in.

[redfast00]

(Blocked by #9)