code: function createDom(str) {
      var name = FRAGMENT_REG.test(str) && RegExp.$1;
      if (!(name in CONTAINERS)) {
        name = '*';
      }
      var container = CONTAINERS[name];
      str = str.replace(/(^\s*)|(\s*$)/g, '');
      container.innerHTML = '' + str;
      var dom = container.childNodes[0];
      container.removeChild(dom);
      return dom;
    }
docs: 创建DOM 节点
  @param  {String} str Dom 字符串
  @return {HTMLElement}  DOM 节点