function rootExperiments(fn) {
  enqueue(function() {
    var data = {};
    var experimentIds = window._vwo_exp_ids;
    if (!experimentIds) return fn();
    each(experimentIds, function(experimentId) {
      var variationName = variation(experimentId);
      if (variationName) data[experimentId] = variationName;
    });
    fn(null, data);
  });
}
Get dictionary of experiment keys and variations.

http://visualwebsiteoptimizer.com/knowledge/integration-of-vwo-with-kissmetrics/

@param {Function} fn
@return {Object}