[5.1.x] Backports for 5.1.0b4 release#349

timgraham wants to merge 6 commits intomongodb:5.1.xmongodb/django-mongodb-backend:5.1.xfrom

timgraham:5.1.0b4-releasetimgraham/django-mongodb-backend:5.1.0b4-releaseCopy head branch name to clipboard