title: django-rest-framework, multitable model inheritance, ModelSerializers and nested serializers
body: <p>I can't find this info in the docs or on the interwebs.<br>
  latest django-rest-framework, django 1.6.5  </p>
  
  <p>How does one create a ModelSerializer that can handle a nested serializers where the nested model is implemented using multitable inheritance?</p>
  
  <p>e.g.</p>
  
  <pre><code>######## MODELS
  class OtherModel(models.Model):
      stuff = models.CharField(max_length=255)
  
  class MyBaseModel(models.Model):
      whaddup = models.CharField(max_length=255)
      other_model = models.ForeignKey(OtherModel)
  
  class ModelA(MyBaseModel):
      attr_a = models.CharField(max_length=255)
  
  class ModelB(MyBaseModel):
      attr_b = models.CharField(max_length=255)
  
  
  ####### SERIALIZERS
  class MyBaseModelSerializer(serializers.ModelSerializer):
      class Meta:
          model=MyBaseModel
  
  class OtherModelSerializer(serializer.ModelSerializer):
      mybasemodel_set = MyBaseModelSerializer(many=True)
  
      class Meta:
          model = OtherModel
  </code></pre>
  
  <p>This obviously doesn't work but illustrates what i'm trying to do here.<br>
  In OtherModelSerializer, I'd like mybasemodel_set to serialize specific represenntations of either ModelA or ModelB depending on what we have.</p>
  
  <p>If it matters, I'm also using django.model_utils and inheritencemanager so i can retrieve a queryset where each instance is already an instance of appropriate subclass.</p>
  
  <p>Thanks</p>