docs(prometheus) disable docs on routes for Prometheus plugin (#1068)
docs(prometheus) disable docs on routes for Prometheus plugin (#1068)

This was a documentation error as the plugin makes sense only at the
service level currently.

ad31ba0888 disabled it for API entity but during the review. @hbagdi
missed to disable it for Route entity as well.
Mashape/getkong.org,Mashape/getkong.org,Mashape/getkong.org