Redis is not nagios, and this only leads to confusion as to why there
is a nagios domain setting on frontend servers; it also leaves the
`redis0` part of the name buried in the template.
Switch to an explicit variable for the redis hostname.
This is more broadly useful than for just Kandra; provide
documentation and means to install Smokescreen for stand-alone
servers, and motivate its use somewhat more.
This old puppet configuration was never really used, and regardless
hardcoded an ancient zulip.net hostname. We fix this to use the
zulipconf system to get the host domain (though not, at present, the
hostname).
The old "zulip_internal" name was from back when Zulip, Inc. had two
distributions of Zulip, the enterprise distribution in puppet/zulip/
and the "internal" SAAS distribution in puppet/zulip_internal. I
think the name is a bit confusing in the new fully open-source Zulip
work, so we're replacing it with "zulip_ops". I don't think the new
name is perfect, but it's better.
In the following commits, we'll delete a bunch of pieces of Zulip,
Inc.'s infrastructure that don't exist anymore and thus are no longer
useful (e.g. the old Trac configuration), with the goal of cleaning
the repository of as much unnecessary content as possible.
