Improve the Djblets coderefs index page.

Review Request #10003 — Created June 6, 2018 and submitted — Latest diff uploaded

Information

Djblets
release-1.0.x
d95cd60...

Reviewers

This adds missing module to the coderefs page, fixes the ordering of
some parts, and introduces more stable references that the upcoming
README file will make use of.

Built the docs and tested the anchors and new pages. Checked for
build errors.