title: Editing model ForeignKey as inline in Django administration?
body: <p>Let's imagine that we have the following Django sample models:</p>
  
  <pre><code>class A(models.Model):
      title = model.CharField(max_length=64)
      b = models.ForeignKey(B, blank=True, null=True)
  
  
  class B(models.Model):
      name = models.CharField(max_length=64)
      age = models.IntegerField()
  </code></pre>
  
  <p>In the Django administration, field <code>A.b</code> is going to be represented as a dropdown widget with controls for adding new <code>B</code> instance, editing it and deleting.</p>
  
  <p>I would like to show the <code>B</code> model similar to the way inlines are shown. However, to show inlines we need a foreign key relation from <code>B.a</code> to <code>A</code>. And I do not want to introduce such relation.</p>
  
  <p>Is it possible to represent <code>B</code> in the <code>A</code> model admin page, as an inline?</p>