add babel-preset-env

package.json

@@ -9,6 +9,7 @@
     "babel-plugin-transform-object-assign": "^6.22.0",
     "babel-plugin-yo-yoify": "^0.3.3",
     "babel-polyfill": "^6.22.0",
+    "babel-preset-env": "^1.6.1",
     "babel-preset-es2015": "^6.24.0",
     "babel-preset-stage-0": "^6.24.1",
     "babelify": "^7.3.0",