Different network topologies

[dmaretskyi]

• [x] Fork discovery-swarm-webrtc
• [x] Move @dxos/protocol to mesh repo
• [x] Provide a way to override swarming engine
• [x] Visualize peer graph using presence plugin
• [x] Fully connected topology
• [ ] Refactor & document existing code
• [ ] Fix/workaround typescript bug and define types for existing code https://github.com/microsoft/TypeScript/issues/41749
• [ ] Star topology
• [ ] RPC protocol extension
• [ ] Display peer graph in devtools

[dmaretskyi]

Closed in favour of https://github.com/dxos/mesh/issues/28