[RAVE-1101] - Introduces Grunt

**NOTE:** #3 should go in first.

This adds Grunt to the project. Eventually we'll use it for a lot more. Presently it just gets the webserver running. An issue right now is the lack of feedback for the `cargo:run` task. This task takes quite some time to get up and running, so you sort of have to 'guess' when it's time to open the app in the browser.

In a future update we can 'sniff' the output of the task on the Vagrantbox to give the user feedback when the app is ready. But that will be v2. @carldanley, do you have any idea how we might implement that functionality?
@mfranklin if you have something in particular you'd like to put here just let me know.