Add ``TestMessagesBackend`` for testing ``django.contrib.messages``.
Add ``TestMessagesBackend`` for testing ``django.contrib.messages``.

When unit testing a django view the ``messages`` middleware
will be missing. This backend will provision a simple
messaging midleware.

Usage::

    from django.test import client
    from us_ignite.common.tests import utils

    factory = client.RequestFactory()
    request = factory.get('/')
    request._messages = utils.TestMessagesBackend(request)

The messages will be added to this simple backend.

us-ignite/us_ignite,us-ignite/us_ignite,us-ignite/us_ignite,us-ignite/us_ignite,us-ignite/us_ignite