[1.8.x] Fixed #25711 -- Updated the project template's include() example.

Referencing URLs by dotted path is a stronger convention than
importing the URLs.

Backport of 179fbab7e0 from master

django/conf/project_template/project_name/urls.py

@@ -10,8 +10,7 @@ Class-based views
     1. Add an import:  from other_app.views import Home
     2. Add a URL to urlpatterns:  url(r'^$', Home.as_view(), name='home')
 Including another URLconf
-    1. Add an import:  from blog import urls as blog_urls
-    2. Add a URL to urlpatterns:  url(r'^blog/', include(blog_urls))
+    1. Add a URL to urlpatterns:  url(r'^blog/', include('blog.urls'))
 """
 from django.conf.urls import include, url
 from django.contrib import admin