Fixed #13397 - Include third level headings in the TOC. thanks cyang for the suggestion, rleland for the patch.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@15073 bcc190cf-cafb-0310-a4f2-bffc1f526a37

docs/contents.txt

@@ -10,7 +10,7 @@ Django documentation contents
     index
 
 .. toctree::
-    :maxdepth: 2
+    :maxdepth: 3
 
     intro/index
     topics/index