Fixed #16606 - Typo in docs/ref/contrib/csrf.txt; thanks selwin.

    1. Add the middleware

       ``'django.middleware.csrf.CsrfViewMiddleware'`` to your list of

       middleware classes, :setting:`MIDDLEWARE_CLASSES`.  (It should come

       and before any view middleware that assume that CSRF attacks have

       before any view middleware that assume that CSRF attacks have

       been dealt with.)

       Alternatively, you can use the decorator