docs: function shuffleArray(array){
      var length = array.length;
      var randomIndex;
      var currentIndex = 0;
      var tmp;
      for (; currentIndex < length; currentIndex++) {
          randomIndex = Math.floor(Math.random() * length);
          tmp = array[currentIndex];
          array[currentIndex] = array[randomIndex];
          array[randomIndex] = tmp;
      }
      return array;
  }