Edited Issue: Provide a way to filter requests to attribute routed controllers to only requests that hit an attribute route [1222]

Today it is cumbersome to use attribute routing with existing routes. For example, the default Web API route may route to a controller with attribute routes, which was probably not intended.

We should provide a way to filter requests to attribute routed controllers to only requests that hit an attribute route.

Ideally, you should be able to have attribute routed controllers and controllers without attribute routes live happily side by side without having to route to each controller explicitly.