[ENHANCEMENT] Add Close connection support to port 80 listener

[elBelgg]

Describe the bug
If you´re using "Close connection" in Default Site, and you have enabled "Enable HTTP server on port 80" it will return 404 instead of closing the connection. If you disable it, it works as expected.

[tobychui]

@elBelgg That is in fact, the default behavior. Let me explain a bit further.

Port 80 listener is design to expose some service to legacy devices that do not support HTTPS, or for WiFi MCUs where resolving TLS / SSL might be too resources heavy. That is why the default site settings do not apply to port 80 as it should only be resolvable on specific enabled host names.

But after seeing this issue, I think it might be nice to add support for close connection as well as it might be useful for preventing IoT device based backdoor attack. So the new behavior will become

1. If default site (primary proxy router, e.g. :443) is set to "Close Connection", requests using hostname with its http proxy rule not enabled port :80 listening will be closed
2. else, it return 404 error (default expected behavior)