Adding babel-preset-stage-2

package.json

@@ -21,6 +21,7 @@
   "dependencies": {
     "babel-plugin-transform-runtime": "^6.23.0",
     "babel-preset-es2015": "^6.24.1",
+    "babel-preset-stage-2": "^6.24.1",
     "element-ui": "^1.4.4",
     "form-backend-validation": "^2.0.1",
     "moment": "^2.18.1",