Ported entire source tree and tests to LDAP mapper

tests/test_mail.py

tests/test_mfa.py

tests/test_oauth2.py

tests/test_role.py

tests/test_selfservice.py

tests/test_user.py

uffd/__init__.py

uffd/ldap.py

uffd/ldap/__init__.py

uffd/ldap/ldap.py

uffd/mail/models.py

uffd/mail/views.py

uffd/mfa/models.py

uffd/mfa/views.py

uffd/oauth2/models.py

uffd/oauth2/views.py

uffd/role/models.py

uffd/role/utils.py

uffd/role/views.py

uffd/selfservice/views.py