v3006.15
Update code to be Py3.7+ to reduce merge forward conflicts
Replace Slack with Discord
[DOCS]: Add topic describing Salt System Architecture for newbies (#58664)
Add a few more nice to have hooks
Update various out-dated links, emails, etc.
Release v3006.15
Document new config option
Remove epub generation for docs
Fix typos (`the the` > `the`) (#52711)
No longer produce man.7
Add new maintenance policy
Fix all Sphinx warnings
Add a `spellcheck` docs build