Add support for Django 1.6

The django.conf.urls.defaults module has been removed in Django 1.6.
The functions include(), patterns() and url() plus handler404,
handler500, are now available through django.conf.urls.

https://docs.djangoproject.com/en/dev/internals/deprecation/

Change-Id: I8d9265e1455d0111edf7596552fa00a3d0b2a97c
Closes-Bug: #1291953