Remove some code that has been dead since newforms-admin was merged, many moons ago.

Author: alex

django/db/models/__init__.py

@@ -15,8 +15,6 @@
 from django.db.models import signals
 from django.utils.decorators import wraps
 
-# Admin stages.
-ADD, CHANGE, BOTH = 1, 2, 3
 
 def permalink(func):
  """