django-admin documentation typo (--v instead of -v)

[Ákos]

At ​https://docs.djangoproject.com/en/1.10/ref/django-admin/#cmdoption-verbosity, the short form of the flag is incorrectly prefixed with two dashes.
The usage output for the command shows only one (and fails with two):

$ python manage.py sqlmigrate --v 3 <app> <migration>
usage: manage.py sqlmigrate [-h] [--version] [-v {0,1,2,3}]
                            [--settings SETTINGS] [--pythonpath PYTHONPATH]
                            [--traceback] [--no-color] [--database DATABASE]
                            [--backwards]
                            app_label migration_name
manage.py sqlmigrate: error: ambiguous option: --v could match --verbosity, --version

[Tim Graham <timograham@…>]

In ea36e745:

Fixed #27988 -- Fixed typo in docs/ref/django-admin.txt.

[Tim Graham <timograham@…>]

In eba34c49:

[1.11.x] Fixed #27988 -- Fixed typo in docs/ref/django-admin.txt.

Backport of ea36e7454c267aab933e92481288e1eab636cd62 from master

[Tim Graham <timograham@…>]

In ab38f4b:

[1.10.x] Fixed #27988 -- Fixed typo in docs/ref/django-admin.txt.

Backport of ea36e7454c267aab933e92481288e1eab636cd62 from master

[Tim Graham <timograham@…>]

In 80f8d7d:

[1.9.x] Fixed #27988 -- Fixed typo in docs/ref/django-admin.txt.

Backport of ea36e7454c267aab933e92481288e1eab636cd62 from master