[1.5.X] Cleaned up contrib.admin install instructions.

   in your :setting:`INSTALLED_APPS` list, add them.

3. Add ``django.contrib.messages.context_processors.messages`` to

   :setting:`TEMPLATE_CONTEXT_PROCESSORS` and

   :class:`~django.contrib.messages.middleware.MessageMiddleware` to

   :setting:`MIDDLEWARE_CLASSES`. (These are both active by default, so

   :setting:`TEMPLATE_CONTEXT_PROCESSORS` as well as

   :class:`django.contrib.auth.middleware.AuthenticationMiddleware` and

   :class:`django.contrib.messages.middleware.MessageMiddleware` to

   :setting:`MIDDLEWARE_CLASSES`. (These are all active by default, so

   you only need to do this if you've manually tweaked the settings.)

4. Determine which of your application's models should be editable in the