User can join new public channel (a topic on our libp2p network)

[holmesworcester]

Once a user is given a user is given a zcash address and viewing key of channel, they can join it.

All users are joined to a "master" channel on startup.

To join a channel:

1. user ensures that they have a unique hidden service for the new channel.
2. user sends a message to the master channel, encrypted to the channel's zcash address, asking for peers for the channel with zcash address A.
3. All peers attempt to decrypt all messages sent to the master channel.
4. Peers respond in a message to channel 18, encrypted to recipient, with a message containing the hidden service addresses they know about.
5. User joins the libp2p/gossipsub network using the unique hidden service.

[holmesworcester]

Update: user asks on "master channel" ("channel 18") to join network with this name. And another user adds them or gives them what they need to join, and they join.