Please work with @medmunds to allow support by django-anymail #1131

I'd like to switch from Mailgun to Twilio/Sendgrid but I need maintained support for Django/Python. Especially since it appears that this library is no longer maintained (#1128 (comment)), please add support for django-anymail. The maintainer just needs an account to be able to test with (anymail/django-anymail#432 (comment)).