Fixed #21712 -- Moved autodiscover() to AdminConfig.ready().

Thanks Marc Tamlyn for the initial version of the patch.

docs/intro/tutorial01.txt

@@ -435,7 +435,7 @@ look like this:
     :filename: mysite/settings.py
 
     INSTALLED_APPS = (
-        'django.contrib.admin',
+        'django.contrib.admin.apps.AdminConfig',
         'django.contrib.auth',
         'django.contrib.contenttypes',
         'django.contrib.sessions',
@@ -444,6 +444,13 @@ look like this:
         'polls',
     )
 
+.. admonition:: Doesn't match what you see?
+
+    If you're seeing ``'django.contrib.admin'`` instead of
+    ``'django.contrib.admin.apps.AdminConfig'``, you're probably using a
+    version of Django that doesn't match this tutorial version.  You'll want
+    to either switch to the older tutorial or the newer Django version.
+
 Now Django knows to include the ``polls`` app. Let's run another command:
 
 .. code-block:: bash

docs/intro/tutorial03.txt

@@ -105,15 +105,20 @@ with:
     :filename: mysite/urls.py
 
     from django.conf.urls import patterns, include, url
-
     from django.contrib import admin
-    admin.autodiscover()
 
     urlpatterns = patterns('',
         url(r'^polls/', include('polls.urls')),
         url(r'^admin/', include(admin.site.urls)),
     )
 
+.. admonition:: Doesn't match what you see?
+
+    If you're seeing ``admin.autodiscover()`` before the definition of
+    ``urlpatterns``, you're probably using a version of Django that doesn't
+    match this tutorial version.  You'll want to either switch to the older
+    tutorial or the newer Django version.
+
 You have now wired an ``index`` view into the URLconf. Go to
 http://localhost:8000/polls/ in your browser, and you should see the text
 "*Hello, world. You're at the polls index.*", which you defined in the
@@ -587,9 +592,7 @@ it to include namespacing:
     :filename: mysite/urls.py
 
     from django.conf.urls import patterns, include, url
-
     from django.contrib import admin
-    admin.autodiscover()
 
     urlpatterns = patterns('',
         url(r'^polls/', include('polls.urls', namespace="polls")),