Fixes py27 django 1.10 dep warnings in core subdomain urls.

Django 1.10 doesn't like using patterns('', ...) and instead
wants the use of a list. It also no longer wants the string path
to a callable and instead wants the callable itself.

Author: Joshua Cole

readthedocs/core/urls/subdomain.py

@@ -4,33 +4,38 @@
 from functools import reduce
 from operator import add
 
-from django.conf.urls import url, patterns
+from django.conf.urls import url
 from django.conf import settings
 from django.conf.urls.static import static
 
+from readthedocs.core.views.serve import (
+    redirect_page_with_filename,
+    redirect_project_slug,
+    serve_docs
+)
+
 from readthedocs.constants import pattern_opts
 
 handler500 = 'readthedocs.core.views.server_error'
 handler404 = 'readthedocs.core.views.server_error_404'
 
-subdomain_urls = patterns(
-    '',  # base view, flake8 complains if it is on the previous line.
+subdomain_urls = [
     url(r'^(?:|projects/(?P<subproject_slug>{project_slug})/)'
         r'page/(?P<filename>.*)$'.format(**pattern_opts),
-        'readthedocs.core.views.serve.redirect_page_with_filename',
+        redirect_page_with_filename,
         name='docs_detail'),
 
     url((r'^(?:|projects/(?P<subproject_slug>{project_slug})/)$').format(**pattern_opts),
-        'readthedocs.core.views.serve.redirect_project_slug',
+        redirect_project_slug,
         name='redirect_project_slug'),
 
     url((r'^(?:|projects/(?P<subproject_slug>{project_slug})/)'
          r'(?P<lang_slug>{lang_slug})/'
          r'(?P<version_slug>{version_slug})/'
          r'(?P<filename>{filename_slug})$'.format(**pattern_opts)),
-        'readthedocs.core.views.serve.serve_docs',
-        name='docs_detail'),
-)
+         serve_docs,
+         name='docs_detail'),
+]
 
 groups = [subdomain_urls]