Mailman: split the django_fedora module

Some imports need to read the config file, which creates a import loop.

roles/mailman/files/django_fedora.py

@@ -13,19 +13,3 @@ def exclude_useless_errors(record):
             if isinstance(exc_value, excluded_class):
                 return False
     return True
-
-
-# Disable local signup
-
-from allauth.account.adapter import DefaultAccountAdapter
-from allauth.socialaccount.adapter import DefaultSocialAccountAdapter
-
-class NoLocalSignUpAdapter(DefaultAccountAdapter):
-
-    def is_open_for_signup(self, request):
-        return False
-
-class SignUpEnabledSocialAdapter(DefaultSocialAccountAdapter):
-
-    def is_open_for_signup(self, request, sociallogin):
-        return True

roles/mailman/files/django_fedora_nosignup.py

@@ -0,0 +1,14 @@
+# Disable local signup
+
+from allauth.account.adapter import DefaultAccountAdapter
+from allauth.socialaccount.adapter import DefaultSocialAccountAdapter
+
+class NoLocalSignUpAdapter(DefaultAccountAdapter):
+
+    def is_open_for_signup(self, request):
+        return False
+
+class SignUpEnabledSocialAdapter(DefaultSocialAccountAdapter):
+
+    def is_open_for_signup(self, request, sociallogin):
+        return True