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- Override ``save_models`` admin methods to add user in history records.
- Add and rename methods in ``RoleMixin``.
- Fix mapping setting check function.
- Implement implicit authorization.
- Add Science/Research classifier.
- Fix bug when id cannot be coerced to right type.
- Add migration 2.
- Improve ``RolePrivilege`` admin.
- Add drag and zoom to role hierarchy graph.
- Update initial migration to reflect code.