ReadTheDocs compatible docstrings

[isaacmg]

We have a lot of antiquated docstrings that don't render well into ReadTheDocs. A kind of grunge (but incredibly useful) task would be to refactor these docstrings into proper ReadTheDocs format. This would allow us to render them effectively...

[codeananda]

I use VS Code and there is an extension which automatically generates docstrings in readthedocs format.

train_transformer_style looks really good, so I assume you'd want them all in that style?

[isaacmg]

Yes if you wanted to open a PR for that it would be really helpful.