Revert "mention usage of postmark.django_backend.EmailBackend"
Revert "mention usage of postmark.django_backend.EmailBackend"

This reverts commit 4d1af638ad375e66282619bcdde46c402bfd378a.

math4youbyusgroupillinois/python-postmark,math4youbyusgroupillinois/python-postmark,themartorana/python-postmark,themartorana/python-postmark