Replace browserify with webpack

I am using [babel-requirejs](https://github.com/hipertracker/requirejs-babel) for having ES6 syntax and modules for my AMD modules. I've loaded Alt from the Bower but something was wrong. I mean, the file `dist/alt-with-addons.js` does not seem to be built correctly. It assumes React is global rather than the UMD module. It is not clear how to use mentioned addons. E.g. how to import `connectToStores` from `alt-with-addons.js`? That file seems to be built in the wrong way. Maybe it would be better to use Webpack to build the correct UMD module?