function uuid() {
  var d = new Date().getTime();
  var uuid = "xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx".replace(/[xy]/g, function (c) {
    var r = (d + Math.random() * 16) % 16 | 0;
    d = Math.floor(d / 16);
    return (c == "x" ? r : r & 0x7 | 0x8).toString(16);
  });
  return uuid;
}
Generates a UUID
based on: http://stackoverflow.com/questions/105034/how-to-create-a-guid-uuid-in-javascript
@returns {string} uuid
@memberof Core