Django-mama-cas

* Fix Django 1.9 compatibility
* Drop support for unsupported Django versions
* Remove ``url`` parameter to ``/logout``
* Change service URL comparison to be more strict
* Fix pgtURL validation not checking against valid services

.. warning::

Support has been dropped for Django 1.4, 1.6 and 1.7, matching Django's
supported versions policy.

* Add new CAS 3 endpoints as aliases
* Update CAS validation error response codes
* Fix ``TARGET`` parameter case for /samlValidate
* Require HTTPS URLs for /samlValidate

* Fix exception when inserting Unicode parameters

* Made defusedxml requirement optional
* Changed stock templates to use Bootstrap
* Enforce CSRF protection on login form
* Fix South migrations for user model foreign keys

* Add Django and South database migrations
* Add example user attribute callbacks
* Fix error when supplying non-string attribute values
* Remove ``MAMA_CAS_USER_ATTRIBUTES`` and ``MAMA_CAS_PROFILE_ATTRIBUTES``

.. warning::

``MAMA_CAS_USER_ATTRIBUTES`` and ``MAMA_CAS_PROFILE_ATTRIBUTES``
have been removed. Use ``MAMA_CAS_ATTRIBUTE_CALLBACKS`` instead.

* Default the asychronous concurrency level to ``2``
* Improve test configuration and output