New Metrics for Status Pages

[kmpaul]

This isn't a complete set of metrics, but I think this now includes all of the metrics I would like to automatically generate for our published packages and repositories.

What I think I would still like to add to the status section of this page is:

• Automatic generation of "Future Short-Term Projects", based on "project"-labeled issues in this repository. I think this can be done with a simple GH GraphQL request, like what is done to generate the number of issues/commits metrics in this PR.
• Automatic generation of "Tutorials" page, based on information that @jukent has. To do that, we need to figure out how to automatically get the "attendance", "title", and "date" for each tutorial, past and future (obviously, attendance would not be displayed for future tutorials).

I think with that, the Status section of this page will be in shape. Then, we need some GitHub Actions/Workflows to keep these pages up-to-date. That is, actions to:

• pull the data down and save new data to this repository (in the data/ directory) nightly,
• generate new plots and metric images from newly updated data,
• generate new markdown pages with updated images, and
• rebuild the site.

Originally posted by @kmpaul in #8 (comment)