[1.8.x] Fixed #25384 -- Ordered imports in newly created migration files

# -*- coding: utf-8 -*-

from __future__ import unicode_literals

from django.db import models, migrations

from django.db import migrations, models

%(imports)s

class Migration(migrations.Migration):

* Fixed autocompletion for options of non-``argparse`` management commands

  (:ticket:`25372`).

* Alphabetized ordering of imports in ``from django.db import migrations,

  models`` statement in newly created migrations (:ticket:`25384`).