Updated networking flow (markdown)

networking-flow.md

@@ -23,6 +23,8 @@ beacon_chain/libp2p_backend.nim:
   - awaits Switch.start() and stores the resulting seq[Future[void]] in Eth2Node.libp2pTransportLoops; nothing further is done with those futures
   - tracesAsyncErrors Eth2Node.runDiscoveryLoop(), which discovers peers and runs `dialPeer` for each discovered peer.
 
+## switch
+
 vendor/nim-libp2p/libp2p/switch.nim:
 
 - Switch.start()
@@ -43,6 +45,8 @@ vendor/nim-libp2p/libp2p/switch.nim:
   - for each MuxerProvider value in Switch.muxers, calls MultistreamSelect.addHandler(MuxerProvider.codec, MuxerProvider)
   - awaits MultistreamSelect.handle(sconn: Connection)
 
+## multistream
+
 vendor/nim-libp2p/libp2p/multistream.nim:
 
 - MultistreamSelect.select(Connection, proto: string)