Change to string to make translation better

EduNetworkBuilder/IPAddress.cs

@@ -223,9 +223,8 @@ namespace EduNetworkBuilder
         }
         public string IPFormat(string gw)
         {
-            string tstring = "IP:" +PadIt(_ip.ToIpString())+
-                " Mask:" + PadIt(_mask.ToIpString())+ 
-                " GW:" + PadIt(gw);
+            string tstring = string.Format("IP:{0} Mask:{1} GW:{2}", 
+                PadIt(_ip.ToIpString()), PadIt(_mask.ToIpString()), PadIt(gw));
             return tstring;
         }
     }