Include scheme in CORS middleware examples
Include scheme in CORS middleware examples

Clarifies CORS documentation based on a comment in

https://github.com/http4s/http4s/issues/2361#issuecomment-457558974

It remains unclear to me if this is a bug or desired change in behavior
so I made no further attempts to modify source or test code.
aeons/http4s,rossabaker/http4s,ChristopherDavenport/http4s,aeons/http4s,ChristopherDavenport/http4s,aeons/http4s,rossabaker/http4s,http4s/http4s,ChristopherDavenport/http4s