This is a pretty big release under the hood, mostly centered around code

cleanup, Django 3.2/4.0 compatibility, and with a lot of fixes to index

management (mostly to faciliate the Index class).
As the vast majority of the work is internal, and some was for the

il-fated Custom Migrations support, those have been left out of the

release notes.

Built the docs. Checked for spelling, build, and link errors.