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- modeladmin mixin that selects the Form class conditionally by
user permission. Custom Form class removes all validation but
could be any Form class. (edc-model-admin)
- add DATA_MANAGER_SUPER group, add codename tuple used by
modeladmin to select Form class by inspecting user perms.
(edc-data-manager)
- add `special` to list of allowed codename prefixes (edc-auth)