Gruntify zippy (bug 927909)

This adds grunt to zippy  to bring stylus to zippy.

Also this automates a bunch of other stuff as well :)

See the docs but in a nutshell:

* use `grunt server` to run zippy's server
* use `grunt server --port=9999` to change the port.
* use `grunt server watch` to run zippy's server and auto jshint and generate css from stylus files as they change.
* use `grunt test` to run both jshint and then nodeunit.