Allow better customization of the /api-docs page.

[kdmccormick]

A lot of value in documentation comes from introduction paragraphs, section structure, etc.

Right now, the /api-docs page is a big list of endpoints.

How can we allow for better customization of the /api-docs page to make it a better experience for consumers of API documentation?

There is a lot of room for discovery and experimentation here.

[kdmccormick]

This will probably help: https://drf-yasg.readthedocs.io/en/stable/custom_ui.html