Upgrade babel, webpack and storybook stack

babel.config.js

@@ -0,0 +1,19 @@
+// Copyright (c) 2015-2016 Yuya Ochiai
+// Copyright (c) 2016-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+module.exports = (api) => { // eslint-disable-line import/no-commonjs
+  api.cache.forever();
+  return {
+    presets: [
+      ['@babel/preset-env', {
+        targets: {
+          browsers: ['Electron >= 2.0'],
+          node: '8.9',
+        },
+      }],
+      '@babel/preset-react',
+    ],
+    plugins: ['@babel/plugin-proposal-object-rest-spread', '@babel/plugin-proposal-class-properties'],
+  };
+};