Update nmap.go to use HTTPS as well instead of HTTP only

Noticed that it always prepends "http", even if HTTPS is enabled. Changed the code to prepend "https" whenever necessary.

pkg/readers/nmap.go

@@ -134,7 +134,7 @@ func (nr *NmapReader) urlsFor(target string, port int) []string {
 	}
 
 	if !nr.Options.NoHTTPS {
-		urls = append(urls, fmt.Sprintf("http://%s:%d", target, port))
+		urls = append(urls, fmt.Sprintf("https://%s:%d", target, port))
 	}
 
 	return urls