Wrong example in docs for reversing Admin URLs using custom instance

[German Larrain]

This example in the ​docs

change_url = urlresolvers.reverse('custom:polls_choice_change', args=(c.id,))

should be

change_url = urlresolvers.reverse('admin:polls_choice_change', args=(c.id,), current_app='custom')

The paragraph introducing the example is correct: "If you want to find a URL in a specific admin instance, provide the name of that instance as a current_app hint to the reverse call"

[Tim Graham <timograham@…>]

In bfe7377adbc0d10dc553a317671c193dce692ad3:

Fixed #21490 -- Fixed custom admin URL reverse example.

Thanks glarrain for the report.

[Tim Graham <timograham@…>]

In af65860c5bc8f5efb76df9078284996cf55114f5:

[1.6.x] Fixed #21490 -- Fixed custom admin URL reverse example.

Thanks glarrain for the report.

Backport of bfe7377adb from master

[Tim Graham <timograham@…>]

In 0934894976042033d74f809cefa229b82cff85f2:

[1.5.x] Fixed #21490 -- Fixed custom admin URL reverse example.

Thanks glarrain for the report.

Backport of bfe7377adb from master

[Tim Graham <timograham@…>]

In 03bc0a8ac5b465a9a1ec88dedb0a2f4bd91dd547:

Fixed typo in previous commit; refs #21490.

[Tim Graham <timograham@…>]

In c0c77955629b27869ba78b91e1cb9b057860a3fc:

[1.5.x] Fixed typo in previous commit; refs #21490.

Backport of 03bc0a8ac5 from master

[Tim Graham <timograham@…>]

In df18cc632cd78d575f434310724034630cc84304:

[1.6.x] Fixed typo in previous commit; refs #21490.

Backport of 03bc0a8ac5 from master