[1.8.x] Fixed #24646 -- Fixed jinja2 example on Python 2.

Backport of d974c89ebb from master

docs/topics/templates.txt

@@ -423,6 +423,8 @@ APIs, you must configure them into the environment.
 
 For example, you can create ``myproject/jinja2.py`` with this content::
 
+    from __future__ import absolute_import  # Python 2 only
+
     from django.contrib.staticfiles.storage import staticfiles_storage
     from django.core.urlresolvers import reverse