host precedence in url.URL.host

gistfile1.txt

	// had to allocate this or the SetBasicAuth below causes a panic
    headers := make(map[string][]string)
    hostPort := fmt.Sprintf("%s:%d", hostname, port)
    fmt.Fprintf(os.Stderr, "adding hostPort:%s:%d:path:%s:\n", hostname, port, path)
	  req := &http.Request{
		Method: "HEAD",
		// Host:  hostPort, // takes precendence over URL.Host
		URL: &url.URL{
			Host:   hostPort,
			Scheme: "http",
			Opaque: path,
		},
		Header: headers,
	}