Converted links to external topics so they use intersphinx extension markup.

This allows to make these links more resilent to changes in the target URLs.
Thanks Jannis for the report and Aymeric Augustin for the patch.

Fixes #16586.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@16720 bcc190cf-cafb-0310-a4f2-bffc1f526a37

docs/conf.py

@@ -26,7 +26,7 @@ needs_sphinx = '1.0'
 
 # Add any Sphinx extension module names here, as strings. They can be extensions
 # coming with Sphinx (named 'sphinx.ext.*') or your custom ones.
-extensions = ["djangodocs"]
+extensions = ["djangodocs", "sphinx.ext.intersphinx"]
 
 # Add any paths that contain templates here, relative to this directory.
 # templates_path = []
@@ -92,6 +92,16 @@ pygments_style = 'trac'
 # Note: exclude_dirnames is new in Sphinx 0.5
 exclude_dirnames = ['.svn']
 
+# Links to Python's docs should reference the most recent version of the 2.x
+# branch, which is located at this URL.
+intersphinx_mapping = {
+    'python': ('http://docs.python.org/2.7', None),
+    'sphinx': ('http://sphinx.pocoo.org/', None),
+}
+
+# Python's docs don't change every week.
+intersphinx_cache_limit = 90 # days
+
 # -- Options for HTML output ---------------------------------------------------
 
 # The theme to use for HTML and HTML Help pages.  See the documentation for