Auto add URLs for each extension

No need to include URLs manually.

Additionally, imports only if urls.py is present. Can be useful when
adding ability to create extensions without URLs (e.g., various
helpers).

geokey/core/urls.py

@@ -11,6 +11,7 @@
     url(r'^oauth2/', include('oauth2_provider.urls', namespace='oauth2_provider')),
     url(r'^admin/account/', include('allauth.urls')),
     url(r'^$', RedirectView.as_view(url='/admin/', permanent=True)),
+    url(r'^', include('geokey.extensions.urls')),
 )
 
 urlpatterns += patterns(

geokey/extensions/urls.py

@@ -0,0 +1,14 @@
+from django.conf.urls import url, include
+
+from geokey.extensions.base import extensions
+
+
+urlpatterns = []
+
+for extension in extensions:
+    try:
+        urls = '%s.urls' % extension
+        __import__(urls)
+        urlpatterns.append(url(r'^', include(urls, namespace=extension)))
+    except ImportError:
+        pass