This takes the scala buildpack and adds NPM and requireJS to it so that play apps can uglify JS files using requireJS much faster!
The changes made can be found here: https://github.com/Hylozoic/heroku-buildpack-scala-with-requirejs/compare/beforeRequireJs...addRequireJS
@see http://stackoverflow.com/a/20694646/2141561 for the SO bug inspiring this hack