@Alias should be a CDI Qualifier

I've been working on the Facet construct internals quite a bit over the last few days, with the way Constraint lookups are performed; I realized that if you wrap a Facet with an Interceptor or Decorator, you can no longer inspect the constraints for that facet because you are in fact inspecting the Java Proxy object, not the Facet class itself.

I believe this change is required to support such behavior.