Build system for JavaScript and CSS files.

The Media Compressor is driven from a single configuration file (media.yml)
which is used to define homogeneous groups of JavaScript and CSS files.

Each group is then exported as a single file.

It uses JSLint to check the JavaScript for errors and YUI Compressor to
compress both types of files.

Typical use case is to edit media.yml and then run:

    java -jar mediacompressor-app-1.0.jar media.yml

This will write the compressed media files into the output directory
specified in media.yml.