code: function once(name, callback, prepend) {
          return on(name, callback, prepend, { once: true });
        }
docs: Binds an event listener to a specific event by name
  and automatically unbind the event once the callback fires.
  
  @method once
  @param {String} name Event name or space separated list of events to bind.
  @param {callback} callback Callback to be executed when the event occurs.
  @param {Boolean} first Optional flag if the event should be prepended. Use this with care.
  @return {Object} Current class instance.
  @example
  instance.once('event', function(e) {
  // Callback logic
  });