Added content release select.

Aims to partially resolve rudyrigot/javascript-angular-starter#3 with the addition of a content release select. Hopefully my "angular-ish" is OK; I'm open to suggestions. As this is a starter kit, in the controller I included an optional page refresh option using `$window.location.href` (commented out). 

FWIW, I'll include the jsFiddle which contains the relevant bits: http://jsfiddle.net/othermachines/Lckpoy5u/

Note that although I'm not a fan of tabs for indentation, the particular file at app/js/controllers.js does contain tabs, so I stuck with that convention in this instance. Cheers -