Fix TypeError due to typo in stream_worker
Catch missing NoNameserves (e.g. when disconnected)
Fix TypeError due to missing argument
Add some helpful debug output when SM resumption is not possible
Harden AsyncQueue a bit
Improve StanzaBroker robustness after reconnects
Implement asynchronous closure of XMLStream
Improve Client robustness during (unclean and clean) reconnects
Handle timeouts while connecting