Add v2.0.0 release notes

[bouweandela]

Add v2.0.0 release notes

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Tasks

• Give this pull request a descriptive title that can be used as a one line summary in a changelog
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[mattiarighi]

It would be good to add the citation to Part II, if it's not too late...

https://gmd.copernicus.org/articles/13/3383/2020/

[bouweandela]

I would really like to try and make the release and build and upload the packages before 6PM. Where would you like to add it?

[mattiarighi]

I'm not sure however whether this should go in the License or in the Recipes section.
Maybe the latter?

[mattiarighi]

We can also do this after the release, since the readthedoc page will be updated with the latest master version, right?

[bouweandela]

We can also do this after the release, since the readthedoc page will be updated with the latest master version, right?

Yes, that would be great, because then I can still make the release today.

I'm not sure however whether this should go in the License or in the Recipes section.

We could add a link to this page under the License

I think we need to document how to cite figures using the _citation.bibtex and _data_citation.txt files (ESMValGroup/ESMValCore#608). Indeed we could also add that paper to the list of references of the recipes that are described in it (on the recipe documentation page as well as in the recipe or diagnostic).

[bouweandela]

Created an issue #1782