Infra: Introduce browserify to transform import/export code in browser

[EthanLin-TWer]

• [ ] introduce browserify, babelify, watchify
• [ ] add npm build script: browserify js/*.js -o dist/bundle.js
• [ ] add npm buildDev script: watchify js/*.js -o dist/bundle.js -t babelify

code to copy:

• https://github.com/linesh-simplicity/peak-chrome-extension/blob/master/package.json
• https://github.com/linesh-simplicity/frontend-nanodegree-arcade-game/blob/master/package.json