User should be able to join multiple, separate waggle/libp2p/ipfs/orbitdb networks

[holmesworcester]

Our "Private communities" epic assumes that users can be part of multiple, separate libp2p networks.

We should prove that this works well under the hood and map out what our options are.

Whatever we do, data needs to move separately on these different networks. And peers on one network shouldn't be able to learn anything about the state of a peer's other networks.