title: django_select2 Caught NameError while rendering: name 'patterns' is not defined
body: <p>I am using django_select2 with my mezzanine project.<br>
  As per doc i follow processes.</p>
  
  <pre>
  #step1 :
  pip install django-select2
  #Step2 :
  url(r'^select2/', include('django_select2.urls')),
  </pre>
  
  <p>But when i reloaded my website i got error</p>
  
  <pre>
  TemplateSyntaxError at /admin/cms_shop/deliverymethod/200/
  
  Caught NameError while rendering: name 'patterns' is not defined
  
  Request Method:     GET
  Request URL:    https://example.net/admin/cms_shop/deliverymethod/200/
  Django Version:     1.3.1
  Exception Type:     TemplateSyntaxError
  Exception Value:    
  
  Caught NameError while rendering: name 'patterns' is not defined
  
  Exception Location:     /home/django/cmsenv/lib/python2.6/site-packages/django_select2/urls.py in , line 5
  Python Executable:  /home/django/cmsenv/bin/python
  Python Version:     2.6.5
  Python Path:    
  
  ['/home/django/core/python/cmsintegration',
   '/home/django/cmsenv/lib/python2.6/site-packages/distribute-0.6.14-py2.6.egg',
   '/home/django/cmsenv/lib/python2.6/site-packages/pip-0.8.3-py2.6.egg',
   '/home/django/cmsenv/lib/python2.6/site-packages/paython-0.0.1-py2.6.egg',
   '/home/django/cmsenv/lib/python2.6/site-packages/django_shop-0.0.11.dev0-py2.6.egg',
   '/home/django/cmsenv/lib/python2.6/site-packages/django_recaptcha-0.0.6-py2.6.egg',
   '/home/django/cmsenv/lib/python2.6',
   '/home/django/cmsenv/lib/python2.6/plat-linux2',
   '/home/django/cmsenv/lib/python2.6/lib-tk',
   '/home/django/cmsenv/lib/python2.6/lib-old',
   '/home/django/cmsenv/lib/python2.6/lib-dynload',
   '/usr/lib/python2.6',
   '/usr/lib/python2.6/plat-linux2',
   '/usr/lib/python2.6/lib-tk',
   '/home/django/cmsenv/lib/python2.6/site-packages',
   '/home/django/cmsenv/lib/python2.6/site-packages/PIL']
  </pre>
  
  <p>Please help me what i am doing wrong.
  my urls.py code is </p>
  
  <pre>
  from django.conf.urls.defaults import *
  from django.contrib import admin
  admin.autodiscover()
  urlpatterns = patterns("",
      url(r'^admin/cms_shop/productimport/delete_selected/([\w]+)/$', delete_selected_import_view, name="cms_shop_delete_selected_import"),
      url("^admin/", include(admin.site.urls)),
      url(r'^select2/', include('django_select2.urls')), 
  )
  </pre>
  
  <p>in settting.py </p>
  
  <pre>
  INSTALLED_APPS = (
      "django.contrib.admin",
      "django.contrib.auth",
      "django.contrib.contenttypes",
      "django.contrib.redirects",
      "django.contrib.sessions",
      "django.contrib.sites",
      "django.contrib.sitemaps",
      "mezzanine.conf",
      "mezzanine.core",
      "mezzanine.blog",
      "mezzanine.pages",
      "mezzanine.generic",
      "userapp",
      "django_select2",
  )
  </pre>