add some custom options & update gitalk and add 2 options

add  some custom options:
*  文章中自动展开目录
*  关闭文章底部自我介绍
*  是否点击链接打开新标签页
update gitalk and add 2 options
* 更新至 1.6.2
* 添加语言选项
* 添加快捷键选项

layout/_script/_comment/gitalk.ejs

@@ -1,6 +1,5 @@
 <% if (typeof(script) !== 'undefined' && script) { %>
   <!-- <link rel="stylesheet" href="https://unpkg.com/gitalk/dist/gitalk.css"> -->
-  <script src="//cdn.jsdelivr.net/npm/[email protected]/dist/gitalk.min.js"></script>
   <script src="//cdn.jsdelivr.net/npm/[email protected]/dist/gitalk.min.js"></script>
   <script src="//cdn.jsdelivr.net/npm/[email protected]/js/md5.min.js"></script>
   <script type="text/javascript">