readthedocs update

[emanuel-schmid]

General improvement of the docs

Changes proposed in this PR:

• Python modules get their own caption in the upper part of the navigation column
• README is duplicated, once for the readthedocs and once for github. This is not sustainable in the long run. But for this release it seems convenient.
• some links from were fixed
• some pydoc cosmetics

This PR circumvents #658

PR Author Checklist

• Read the Contribution Guide
• Correct target branch selected (if unsure, select develop)
• Source branch up-to-date with target branch
• Documentation updated
• Tests updated
• Tests passing
• No new linter issues
• Changelog updated

PR Reviewer Checklist

• Read the Contribution Guide
• CLIMADA Reviewer Checklist passed
• Tests passing
• No new linter issues

[emanuel-schmid]

#658 has not been addressed yet because, afaik, it's the only place where we tell how we want to be cited.
Which should be part of the documentation - shouldn't it?

[peanutfun]

We can of course add the information how we wish to be cited to the documentation index. It would also be nice to add a separate documentation page that lists all publications on Climada.

[peanutfun]

Why not rename "Python Modules" to "API Reference", and leave it in the original toctree? I would not add this as a separate toctree with caption because I don't see that we add any other entries in the future. And a separate caption for only a single item does not make much sense to me

[emanuel-schmid]

1. It definitely deserves its own section. (I agree that a single item is a wee bit awkward. I wanted to make the section title [API Reference] interactive and unfold subsections only when I actually click on it, but I couldn't figure out how to do that.)
2. For making navigation easier. When I browse through the API reference and its navigation is at the bottom of the page I lose context through re-rendering whenever I click on a module. When it's on top, the unfolded doc-tree is stable.

[emanuel-schmid]

We can of course add the information how we wish to be cited to the documentation index. It would also be nice to add a separate documentation page that lists all publications on Climada.

👍 True. But not yet in 3.3, I'd say. 😁

[emanuel-schmid]

@peanutfun: Do you mind if I merge now?