In particular, this improves:
* The explanation of how data is mapped into Zulip
* The explanation of what is printed out by `manage.py query_ldap`
* Makes sure users create their first account with EmailAuthBackend.
The term "username" confusingly refers both to the Django concept of
"username" (meaning "the name the user types into the login form") and
a concept the admin presumably already has in their existing
environment; which may or may not be the same thing, and in fact this
is where we document the admin's choice of whether and how they should
correspond. The Django concept in particular isn't obvious, and is
counterintuitive when it means something like an email address.
Explicitly explain the Django "username" concept, under the name of
"Zulip username" to take responsibility for our choice of how it's
exposed in the settings interface. Then use an explicit qualifier,
like "LDAP username", whenever referring to some other notion of
username. And make a pass over this whole side of the instructions,
in particular for consistent handling of these concepts.
Expand on a few things that tend to confuse people (especially the
`%(user)s` thing); move the `LDAPSearchUnion` example out to docs;
adjust the instructions to fit a bit better in their new docs/ home.
This makes it easier to iterate on these, and to expand supplemental
information (like troubleshooting, or unusual configurations) without
further straining the already-dauntingly-long settings.py.
It also makes it easier to consult the instructions while editing the
secrets file, or testing things, etc. -- most admins will find it more
natural to keep a browser open somewhere than a second terminal.
Hopefully this version makes it somewhat clearer how the different
methods relate to each other, how to choose between them, what
`ZulipRemoteUserBackend` is for, and how the latter works.
This commit helps reduce clutter on the navigation sidebar.
Creates new directories and moves relevant files into them.
Modifies index.rst, symlinks, and image paths accordingly.
This commit also enables expandable/collapsible navigation items,
renames files in docs/development and docs/production,
modifies /tools/test-documentation so that it overrides a theme setting,
Also updates links to other docs, file paths in the codebase that point
to developer documents, and files that should be excluded from lint tests.
Note that this commit does not update direct links to
zulip.readthedocs.io in the codebase; those will be resolved in an
upcoming follow-up commit (it'll be easier to verify all the links
once this is merged and ReadTheDocs is updated).
Fixes#5265.