title: Django REST depth = 1 without quit the field form
body: <p>Model:</p>
  
  <pre><code>class StoreSettings(models.Model):
      slider_images = models.ManyToMany......
  </code></pre>
  
  <p>In Serializer I have this:</p>
  
  <pre><code>class SettingsSerializer(serializers.ModelSerializer):
      class Meta:
          model = StoreSettings
          fields = ('slider_images', )
          depth = 1
  </code></pre>
  
  <p>Adding <code>depth = 1</code> The Multiple choice field is removed of the Django Rest form</p>
  
  <p>I want to add <code>depth = 1</code> but, with the form like It didn't happend</p>
  
  <p>Thanks</p>