This only changes the script-layer API, but keeps the std::string host
in the C++ layer's ServerOptions. Mostly because the ixwebsocket library
takes host as std::string. Also, maybe at some point we'd want to
support something scheme-based like unix:///var/run/zeek.sock and placing
that in a string could not be totally wrong.
Add tests for IPV6, too.
Explicitly notify the internal thread about the shutdown via the
inproc socket pair. This ensures that the internal thread processes
all previous messages on the inproc socket before terminating.
This fixes the scenario where a backend is created, a few messages published
and then immediately terminated as can be done with WebSocket clients.
Previously, some of the messages published might have still been in the
inproc socket's queue and were simply discarded.
Adds the same test for Broker and ZeroMQ backends.
