'AlterField should optimize into CreateModel.'

def test_create_model_alter_field(self):

    managers = [('objects', EmptyManager())]
    self.assertOptimizesTo([migrations.CreateModel(name='Foo', fields=[('name', models.CharField(max_length=255))], options={'verbose_name': 'Foo'}, bases=(UnicodeModel,), managers=managers), migrations.AlterField('Foo', 'name', models.IntegerField())], [migrations.CreateModel(name='Foo', fields=[('name', models.IntegerField())], options={'verbose_name': 'Foo'}, bases=(UnicodeModel,), managers=managers)])
