Adding babel-polyfill to fix errors

.babelrc

@@ -1,3 +1,4 @@
 {
-  "presets": ["es2015"]
+  "presets": ["es2015"],
+  "plugins": ["transform-runtime"]
 }

gulpfile.js

@@ -116,6 +116,7 @@ gulp.task('scripts', 'Build scripts into ./build directory', function() {
   return browserify(config.browserify)
     .transform(canopy)
     .transform(babelify)
+    .add(require.resolve('babel-polyfill'))
     .add('./src/js/main.js')
     .bundle()
     .on('error', notify.onError())

package.json

@@ -10,7 +10,10 @@
   "license": "MIT",
   "private": true,
   "devDependencies": {
+    "babel-plugin-transform-runtime": "^6.1.2",
+    "babel-polyfill": "^6.0.16",
     "babel-preset-es2015": "^6.0.14",
+    "babel-runtime": "^6.0.14",
     "babelify": "^7.1.0",
     "browserify": "^12.0.1",
     "canopy": "^0.2.0",