title: django.db.migrations.RenameModel and AutoField sequence name
body: <p>I use Django 1.8.7 and PostgreSQL and had the following model:</p>
  
  <pre><code>class Permission(models.Model):
  
      name = models.CharField(max_length=255)
      template = models.ForeignKey(Template, related_name='permissions')
  </code></pre>
  
  <p>The I have added RenameModel operation:</p>
  
  <pre><code>    migrations.RenameModel(
          old_name='Permission',
          new_name='TemplatePermission',
      ),
  </code></pre>
  
  <p>Looks that all work OK but sequence name for TemplatePermission.id field still myapp_permission_id_seq:</p>
  
  <pre><code>postgres=# \d+ myapp_templatepermission
                                              Table "public.myapp_templatepermission"
     Column    |          Type          |                          Modifiers                           | Storage  | Description 
  -------------+------------------------+--------------------------------------------------------------+----------+-------------
   id          | integer                | not null default nextval('myapp_permission_id_seq'::regclass) | plain    | 
  
  ...
  </code></pre>
  
  <p>It there right way to rename sequence? Is it a bug in Django (I had found very similar bug report and patch for Django 1.8.x and Oracle)?</p>