[WFLY-3468] reconnect if connecting to the host-controller fails

https://issues.jboss.org/browse/WFLY-3468
I don't much like making this configurable, although it's no big deal. Some sort of delay is good though, so the thread reading stdin and calling asyncReconnect doesn't get starved by continual resubmissions of ReconnectRunner. I know that's unlikely though...