Fixed some formatting that wasn't displaying correctly in readthedocs

[thibaultmol]

I fixed some formatting that caused a section not to appear correctly on readthedocs:

And while at it, I made some general improvements in that area of the docs.

btw two questions:

• Is the plan to have the Trello JSON duplicate in the docs like this?
• why is the import/export doc not in readthedocs?

[github-actions]

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