Login and logout views for the browsable API.

Add these to your root URLconf if you're using the browsable API and your API requires authentication:

urlpatterns = [
    url(r'^auth/', include('lino.modlib.restful.urls', namespace='rest_framework'))

In Django versions older than 1.9, the urls must be namespaced as 'rest_framework', and you should make sure your authentication settings include SessionAuthentication.