Added some initial documentation on adding customized commands to django-admin.py.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@5925 bcc190cf-cafb-0310-a4f2-bffc1f526a37

docs/django-admin.txt

@@ -603,3 +603,32 @@ distribution. It enables tab-completion of ``django-admin.py`` and
     * Press [TAB] to see all available options.
     * Type ``sql``, then [TAB], to see all available options whose names start
       with ``sql``.
+
+Customized actions
+==================
+
+**New in Django development version**
+
+If you want to add an action of your own to ``manage.py``, you can.
+Simply add a ``management/commands`` directory to your application.
+Each python file in that directory will be discovered and registered as
+a command that can be executed as an action when you run ``manage.py``::
+
+    /fancy_blog
+        __init__.py
+        models.py
+        /management
+            __init__.py
+            /commands
+                __init__.py
+                explode.py
+        views.py
+        
+In this example, ``explode`` command will be made available to any project
+that includes the ``fancy_blog`` application in ``settings.INSTALLED_APPS``.
+
+The ``explode.py`` file has only one requirement -- it must define a class
+called ``Command`` that extends ``django.core.management.base.BaseCommand``.
+
+For more details on how to define your own commands, look at the code for the
+existing ``django-admin.py`` commands, in ``/django/core/management/commands``.