How to browserify & uglify ES2015 code

ES2015-uglifyjs2-browserify.sh

## Install browserify:
$ npm install -g browserify

# Install uglify-js:
### First remove already installed one:
$ npm remove uglify-js -g
### Install the ES2015 compatible version from 'harmony' branch:
$ npm install -g https://github.com/mishoo/UglifyJS2.git#harmony

# Try uglify of ES2015 code:
### 'input.js' is written in ES2015 
$ uglifyjs --compress --mangle -- input.js

# browserify collaborate with uglifyjs:
$ browserify ./public/javascripts/app.js | uglifyjs > ./public/javascripts/bundle.min.js

# example output:
# bundle.js 2.4M (non-uglified)
# bundle.min.js 748K (uglified) <- Awesome!