Django-mama-cas

* Drop support for unsupported Python versions (thanks stsewd!)
* In the ValidationResponse, add support to serialize values of type list (thanks tarunpaul!)
* Don't stop the rest of sign out requests if one fails (thanks stsewd!)
* Changed password field to not strip its data (thanks pmayer!)
* Other minor fixes (thanks enewhuis!)

* Added Portuguese translation (thanks vitorcarareto!)
* Added Icelandic translation (thanks barnabywalters!)
* Updated Chinese translation (thanks overcat!)


.. warning::

Support has been dropped for Python 2.

Support has been dropped for Django 1.8, 1.9, 1.10, 1.11 and 2.0, matching Django's
supported versions policy.

* Official Django 2.0+ support (thanks manelclos!)
* Add setting to enable custom service backends (thanks rebkwok!)
* Fix XML encoding for SAML responses (thanks ljupchokotev!)

* Official Django 1.11 support (thanks pbaehr!)
* Allow multiple attribute values in SAML responses (thanks richardjs!)
* Replace gevent with requests-futures to eliminate monkeypatching
* Add settings to completely switch out templates (thanks lorenmh!)

* Improve output of ``checkservice`` management command
* Validate proxy endpoint prior to executing callback
* Handle exceptions in attribute callbacks

* Add Django 1.10 compatibility
* Add per-service configuration with ``MAMA_CAS_SERVICES``
* Add allowing/disallowing proxying for each service
* Add pgtUrl identifier pattern validation
* Add configurable logout URL for each service
* Add ``checkservice`` management command for testing service identifiers
* Reverted logout ``url`` parameter removal for older client compatibility
* Fix direct access of ``User`` model in test suite

.. warning::

``MAMA_CAS_VALID_SERVICES``, ``MAMA_CAS_ATTRIBUTE_CALLBACKS``,
and ``MAMA_CAS_ENABLE_SINGLE_SIGN_OUT`` have been deprecated in
favor of per-service configuration with ``MAMA_CAS_SERVICES``.

* Fix SLO request encoding