* [NOD-1124] Rename Peer to Connection (because Peer is a business logic term)
* [NOD-1124] Implement Close for Router.
* [NOD-1124] Add SetPeerDisconnectedHandler.
* [NOD-1124] Remove mentions of "peer" from the netadapter package.
* [NOD-1124] Handle errors/stopping in netadapter.
* [NOD-1124] Remove netadapter.Connection.
* [NOD-1124] Add startSendLoop.
* [NOD-1124] Implement network IDs.
* [NOD-1124] Implement a map between IDs and routes.
* [NOD-1124] Implement Broadcast.
* [NOD-1124] Fix rename error.
* [NOD-1124] Fix copy+paste error.
* [NOD-1124] Change the type of NetAdapter.stop to uint32.
* [NOD-1124] If NetAdapter is stopped more than once, return an error.
* [NOD-1124] Add an error case to RouteInputMessage.
* [NOD-1124] Rename CreateID to NewID.
* [NOD-1124] Spawn from outside startReceiveLoop and startSendLoop.
* [NOD-1124] Fix a comment.
* [NOD-1124] Replace break with for condition.
* [NOD-1124] Don't disconnect from disconnected peers.
* [NOD-1124] Fix a for condition.
* [NOD-1124] Handle an error.
* [NOD-1124] Begin implementing netadapter.
* [NOD-1124] Implementing a stub gRPC server..
* [NOD-1124] Construct the server inside the netadapter.
* [NOD-1124] Rewrite protocol.go to fit with the new netAdapter model.
* [NOD-1124] Wrap a connection in Peer.
* [NOD-1124] Add a peerstate object.
* [NOD-1124] Remove the peerstate object.
* [NOD-1124] Remove router out of Peer.
* [NOD-1124] Tag a TODO.
* [NOD-1124] Return an error out of AddRoute if a route already exists for some message type.
* [NOD-1124] Rename the package grpc to grpcserver.
* [NOD-1124] Extracted newConnectionHandler into a type.
* [NOD-1124] Extract routerInitializer into a type.
* [NOD-1124] Panic/Add TODOs everywhere that isn't implemented.
* [NOD-1124] Improve the NetAdapter comment.
* [NOD-1124] Rename NewConnectionHandler to PeerConnectedHandler.
* [NOD-1124] Rename buildRouterInitializer to newRouterInitializer.
* [NOD-1124] Remove unreachable code.
* [NOD-1124] Make go vet happy.
