Add a python-dateutil dependency to Djblets 1.x.

Review Request #9931 — Created May 11, 2018 and submitted — Latest diff uploaded

Information

Djblets
release-1.0.x
44f7f76...

Reviewers

This adds a dependency on python-dateutil to Djblets 1.x. We now need
this here for consent tracking. We already include a dependency on
python-dateutil (though a newer version) on Djblets 2.x.

This is the same version used by Review Board, helping packagers keep
things consistent.

Ran ./setup.py develop and verified it was fetching python-dateutil.