Migrate test suite to 389ds

Currently the test suite uses openldap as a server. However, we'd like to be able to run it in RHEL/CentOS, which means that it ought to be done with 389ds.

n.b.: While it's tempting to use freeipa rather than doing this by hand, there are two large problems with that. First, freeipa takes *forever* to download and install because it's setting up so much else that we don't need (we just need a KDC). Second, freeipa's server isn't usable in distros that aren't Fedora-like, while gssproxy is; within reason, I'd like to keep parity between where we can run our code and our tests.

Start by examining the test suite's current OpenLDAP setup and its test entry points; the issue does not name files or commands. Migrate the test server to 389ds while preserving the stated RHEL/CentOS goal and compatibility with non-Fedora-like environments, then run the complete test suite against the new setup.

Written by the indexing model from the issue text.