As a content admin, I want document data exports synchronized to github so that there is a publicly accessible, versioned copy of project data available for researchers.

[rlskoeser]

testing notes

• make some changes in the database to content included in data exports (documents, fragments, footnotes, sources)
• see if they are reflected in the exports synchronized to github at https://github.com/Princeton-CDH/test-geniza-metadata (currently running every 30 minutes)

This version does not include co-author commits tracking who made changes (that will be added in the next round)

dev notes

• reimplement existing admin document data export with django-import-export
• adjust fields as needed by existing issues (to be added here)
• make a public version of the export that exempts admin fields (notes, admin url, ...)
• write a manage command that can generate the public export and sync to a configured github repo #1218

[quadrismegistus]

Fields in adminexporter not to be included in public: notes, needs_review, url_admin, status

Make sure that status == public as well

[rlskoeser]

some initial testing notes:

• we're committing even when there are no changes, so we're getting a lot of empty commit messages
• let's make the commit message more like the annotation backup; no need to include the date since that's elsewhere in the commit metadata

[kseniaryzhova]

@rlskoeser I see my commits, it works! Closing!