code: function moveChild(tagName, newPos) {
        var parent = this.parent;
        var tags;
        // no parent no move
        if (!parent) { return }
  
        tags = parent.tags[tagName];
  
        if (isArray(tags))
          { tags.splice(newPos, 0, tags.splice(tags.indexOf(this), 1)[0]); }
        else { arrayishAdd(parent.tags, tagName, this); }
      }
docs: Move the position of a custom tag in its parent tag
  @this Tag
  @param   { String } tagName - key where the tag was stored
  @param   { Number } newPos - index where the new tag will be stored