Move CORS functionality to CorsMixin class and add a TraceMixin also

[Jaymon]

I don't think cors support needs to be there by default so the functionality can be moved to a mixin class and then I can add a trace mixin class also.

TRACE information

• https://http.dev/trace
• what is http trace method
• https://developer.mozilla.org/en-US/docs/Web/HTTP/Methods/TRACE