change to use class

Author: jochen-testingbot

.eslintrc.js

@@ -1,6 +1,10 @@
 module.exports = {
     "env": {
-        "node": true
+        "node": true,
+        "es6": true
+    },
+    "parserOptions": {
+        "ecmaVersion": 2015
     },
     "extends": "eslint:recommended",
     "rules": {