title: How to show only one image in Django admin inline
body: <p>I'm using <code>django.contrib.admin</code> in one of my apps.</p>
  
  <p>my models:</p>
  
  <pre><code>class Gallery(models.Model):
      location = models.ForeignKey(Location)
      date = models.CharField(max_length = 15)
  
  class Image(models.Model):
      gallery = models.ForeignKey(Gallery)
      name = models.CharField(max_length=35)
      image = ImageField(upload_to='songs')
  </code></pre>
  
  <p>my <code>admin.py</code>:</p>
  
  <pre><code>class ImageInline(admin.StackedInline):
      model           = Image
  
  class GalleryAdmin(admin.ModelAdmin):
      inlines = [ ImageInline, ]
  </code></pre>
  
  <p>In the admin section I'm now able to create a gallery and add images on the same page. By default django shows three image upload forms. How can I change it to only one?</p>