switch url to id in invitation process

client/server.go

@@ -112,7 +112,7 @@ func (ints *InternalServer) BuildToServerMessageInvitation(invitation *meowlib.C
 	msg.From = ints.Me.Public
 	inv.Password = password
 	inv.Timeout = int32(timeout)
-	inv.Urllen = int32(urllen)
+	inv.Idlen = int32(urllen)
 	inv.Payload = payload
 	msg.Invitation = &inv
 	return &msg, nil