Connect to localhost instead of the socket's binding address.

The bound address is 0.0.0.0 which usually implies all
available interfaces, which makes sense when listening
for something. However, when connecting to an address,
a specific address needs to be targeted. Hopefully, any
properly configured computer should have `localhost`
pointing to its loopback interface. Fixes #64

tests/test_connection.py

@@ -21,7 +21,8 @@
 class _ConnectTest(unittest.TestCase):
     def _test_connect(self, client_version=None, server_version=None):
         server = FakeServer(minecraft_version=server_version)
-        addr, port = server.listen_socket.getsockname()
+        addr = "localhost"
+        port = server.listen_socket.getsockname()[1]
 
         cond = threading.Condition()