add dir under /about/

docs/.vuepress/config.js

@@ -162,6 +162,12 @@ module.exports = {
           children: getSidebarByCategory('appdev','en')
         }
       ],
+      '/about/': [
+        ['','项目概况'],
+        ['xuos','XiUOS操作系统计划'],
+        ['contact','联系方式'],
+        ['license','开源协议']
+      ]
     }
   },