Allow set default convention endpoints behavior

[picodotdev]

Currently a page with a route have two URLs, Tapestry convention and route assigned URLs.

@Route("/{0}/event/{1}")
public class Event {
}

For this example Event page has two URLs:

• Convention: /event/seo-friendly-slug/42
• Route: /seo-friendly-slug/event/42

This may be not the desired in a website for not have duplicated content. Also if some time later a page is assigned a route the convention URL may be desired to be updated with a redirect or a not found status code.

This issue is for allow to configure de behavior of the Tapestry convention URL when a page has a route. Possible values can be:

• Default: same page with two URLs, current behavior.
• Redirect: when convention URL is requested a redirect is returned to route URL.
• Not Found: when convention URL is requested a HTTP 404 error is returned.