Import external pages from other sources

This is an issue intended as an all-encompassing tracker for the various groups of pages that "live" in other places across CHAOSS and need to be imported into the site.

See also this wikipage i started to help try and keep track of what content is imported and what isnt:

https://github.com/chaoss/hugo/wiki/Pages-that-are-sourced-from-elsewhere

Start with the linked CHAOSS wiki page, “Pages that are sourced from elsewhere,” and review which page groups it tracks. Compare that inventory with the current site to identify what remains external. Done means the relevant external pages have been imported into the site and the tracking information is up to date.

Written by the indexing model from the issue text.