remove use of django.conf.url.patterns in django > 1.8
remove use of django.conf.url.patterns in django > 1.8

Resolve

```
/home/vagrant/.virtualenvs/djangoproj/src/django-robots/django_robots/urls.py:5: RemovedInDjango110Warning: django.conf.urls.patterns() is deprecated and will be removed in Django 1.10. Update your urlpatterns to be a list of django.conf.urls.url() instances instead.
  url(r'^$', TemplateView.as_view(template_name='robots/robots.txt', content_type='text/plain'), name='robots'),
```
jbergantine/django-robots