Installs and configures connect-assets module

With this module now there’s available an assets pipeline for
CoffeeScript and Stylus.
Adds Backbone, Marionette, jQuery and Underscore scripts
Requires Backbone, Underscore, Marionette and jQuery scripts on the main script

This will make the scripts tags for each one available on the HTML
Merge pull request #1 from adrrian17/assets-pipeline

Assets pipeline