Add how-to-cite to portal

[jukent]

Do we want how to cite in the long page or on a separate page?

I want to add this to the footer as well, but I think that is done in the sphinx-pythia-theme repo. I need to do more investigation on the cite infrastructure, but this is a good first step.

Please give your review on the text as well as location.

Related to #306

[github-actions]

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[jukent]

Which section of the footer would it best fit in? I'm leaning towards under "About"

[jukent]

Similarly, do we want this in the top nav bar?

[jukent]

Looks like I'd have to change it in the portal, foundations, and cookbook gallery footer-menu:
https://github.com/ProjectPythia/projectpythia.github.io/blob/main/portal/_templates/footer-menu.html
https://github.com/ProjectPythia/pythia-foundations/blob/main/_templates/footer-menu.html
https://github.com/ProjectPythia/cookbook-gallery/blob/main/site/_templates/footer-menu.html

Looking at this, should we remove the discussions and replace with a link to Pangeo discourse?

[jukent]

See ProjectPythia/cookbook-gallery#170 and ProjectPythia/pythia-foundations#418 for making these changes in Foundations and Cookbooks

[brian-rose]

I like the location of the "How to Cite" section at the bottom of the single home page. It makes sense to me.

I notice a number of places where there are now dead links because we removed the Team section (#346). I'll open a new issue about that. Unfortunately our link checker doesn't fail on missing internal links to page anchors so there's no notification about that.

[brian-rose]

Opened #349 to track the newly broken links