Fix configuration loading on Node v0.12.x and io.js.

lib/app/addons/rs/config.js

@@ -145,7 +145,7 @@ YUI.add('addon-rs-config', function(Y, NAME) {
                             throw new Error(parseErr);
                         }
                     } catch (err) {
-                        if (err.errno !== 34) { // if the error was not "no such file or directory" report it
+                        if (err.code !== "ENOENT") { // if the error was not "no such file or directory" report it
                             throw new Error("Error parsing file: " + fullPath + "\n" + err);
                         }
                     }