We can now autoconnect via parameter on web, e.g. `freq=430.200`, which
then autoconnects to that frequency, creating it when it is not already
created. We also now reconnect on connection failure and display the
connection state down below.
We now send out messages to all participants at the same time (or more
or less, as asyncio permits). To not fail in case we can't send the
message to one player, we ignore send-exceptions in these occasions and
hope that the `for data in self.websocket` in _handle_client() will
throw an error and kick the client out of our game.