dev Middleware docs sample isn't up to date with dev startproject template

[Keryn Knight <django@…>]

​The middleware page includes an example of what startproject would output; at the time of writing, it is:

MIDDLEWARE_CLASSES = (
    'django.middleware.common.CommonMiddleware',
    'django.contrib.sessions.middleware.SessionMiddleware',
    'django.middleware.csrf.CsrfViewMiddleware',
    'django.contrib.auth.middleware.AuthenticationMiddleware',
    'django.contrib.messages.middleware.MessageMiddleware',
)

This doesn't seem to jive with the ​MIDDLEWARE_CLASSES in the project template, which includes django.middleware.clickjacking.XFrameOptionsMiddlewareby default for the first time.

[Tim Graham <timograham@…>]

In 26c4bd38acd4c1b5125eaa381420c2ca5603bd39:

Fixed #20862 -- Updated startproject MIDDLEWARE_CLASSES in docs.

Thanks Keryn Knight.

[Tim Graham <timograham@…>]

In 06f484dcf9984f2a2223f20422e130844c246800:

[1.6.x] Fixed #20862 -- Updated startproject MIDDLEWARE_CLASSES in docs.

Thanks Keryn Knight.

Backport of 26c4bd38ac from master