Add example for database test settings

[m4r0v3r]

Hello,

The documentation for the Database Test Settings is lacking and can leave users such as me confused, if a simple example such as this was included it would help :)

here:

​https://docs.djangoproject.com/en/1.8/ref/settings/#std:setting-DATABASE-TEST

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.postgresql_psycopg2',
        'USER': 'jenkins',
        'NAME': 'django',
        'TEST': {
            'NAME': 'test_another_name',
        },
    },
}

Thanks to MarkusH for the example and help :)

[Tim Graham]

For future reference, don't forget to add a link to ​the pull request and check "Has patch" so it appears in the review queue.

[Tim Graham <timograham@…>]

In cf99bae:

Fixed #25351 -- Added example for database test settings to docs.

[Tim Graham <timograham@…>]

In d32edd8:

[1.8.x] Fixed #25351 -- Added example for database test settings to docs.

Backport of cf99bae53af2ed8f73622bc8a8ed0331c272fda3 from master