Clients that will be at the ClientProtoInfo protocol level (or above)
will now receive an asynchronous INFO protocol when the server
they connect to adds a *new* route. This means that when the cluster
adds a new server, all clients in the cluster should now be notified
of this new addition.
Don't check what is sent back. The point is that the client should be fully initialized at this point.
We can't ensure using metrics that the "check" connection is gone since in some tests, the server is started and clients auto-reconnect to it.
For tests that depend on the number of clients connected (such as the monitor one), have specific code for those tests.
- The raw connection used to check that the server is started now consumes the INFO and sends PING and consumes PONG before returning.
- The route test needs to make sure that the client connection has client id 2. Using PING/PONG before creating route connection to make sure of that.
* Add server.GetListenEndpoint() to return options' host and port when server is ready to accept client connections. The server can be asked to pick a random port. This function returns a string of the form "host:port" with the port selected by the net.Listen() call.
* Replace the use of server.Addr() with above function to connect to the starting server (using net.Dial) to check for success. The original issue was that, when no hostname is specified in the configuration, the server uses 0.0.0.0 for the listen address. However, server.Addr() would return "[::]", even on a machine with IPv6 disabled, which would cause the net.Dial call to fail with "network unreachable".
