function lazyReverse() {
      var filtered = this.filtered,
          result = filtered ? new LazyWrapper(this) : this.clone();

      result.dir = this.dir * -1;
      result.filtered = filtered;
      return result;
    }
Reverses the direction of lazy iteration.

@private
@name reverse
@memberOf LazyWrapper
@returns {Object} Returns the new reversed `LazyWrapper` object.