Handle localhost distributed setups properly (#8577)

Fixes an issue reported by @klauspost and @vadmeste

This PR also allows users to expand their clusters
from single node XL deployment to distributed mode.

pkg/net/port.go

@@ -31,6 +31,12 @@ func (p Port) String() string {
 
 // ParsePort - parses string into Port
 func ParsePort(s string) (p Port, err error) {
+	if s == "https" {
+		return Port(443), nil
+	} else if s == "http" {
+		return Port(80), nil
+	}
+
 	var i int
 	if i, err = strconv.Atoi(s); err != nil {
 		return p, errors.New("invalid port number")