Adding parameter replacement

Provides token replacement for attribute routing template using a syntax like:

`api/[controller]/{id?}`

With this change the use of controller and action as parameters in attribute routes is disallowed, and will reported as an error. This is the cool new way to do it, which will provide more consistent behavior, and better performance.

Majority of the changes here are to provide a good experience for reporting errors across all the attribute routes.
Yes and that could be the case. I didn't realize we ignore unknown segments and wonder if that is good behavior. I think I'd rather detect all segments and explode for un-replaceable segments to inform the user that they are using a special syntax, but are using it incorrectly.