Improve documentation building

[mcocdawc]

• [ ] stricter checks
• [ ] bibtex

Stricter checks

the documentation should be built with stricter error checking

        make html SPHINXOPTS="-W --keep-going -n"

this should be part of the CI pipeline, not part of the read the docs process.

Bibtex

It should use bibtex for references. https://sphinxcontrib-bibtex.readthedocs.io/en/latest/