allow users to login with username or email address (#1510)

we commonly get confusion as people either forget their username or do not realize that they have one.

this allows for users to login with either their username or email address

Author: ewdurbin

pydotorg/settings/base.py

@@ -74,6 +74,7 @@
 ACCOUNT_EMAIL_REQUIRED = True
 ACCOUNT_UNIQUE_EMAIL = True
 ACCOUNT_EMAIL_VERIFICATION = 'mandatory'
+ACCOUNT_AUTHENTICATION_METHOD = 'username_email'
 SOCIALACCOUNT_EMAIL_REQUIRED = True
 SOCIALACCOUNT_EMAIL_VERIFICATION = True
 SOCIALACCOUNT_QUERY_EMAIL = True