new: auxiliary tool

docs/.vuepress/config.js

@@ -31,6 +31,10 @@ module.exports = {
         text: '扩展阅读',
         link: '/more/'
       },
+      {
+        text: '辅助工具',
+        link: '/tools/'
+      },
       {
         text: '人之初',
         link: '/donate/'

docs/tools/README.md

@@ -0,0 +1,10 @@
+# 查看源码的辅助工具
+
+## vue-template-compiler-palyground
+
+* 作用：帮助你方便的查看 `Vue` 模板经过编译之后所生成的 `AST`、`render`、`staticRenderFns` 以及编译的错误信息 `errors`
+
+* Github：[vue-template-compiler-palyground](https://github.com/HcySunYang/vue-template-compiler-playground)
+
+* 在线使用：[http://hcysun.me/vue-template-compiler-playground/](http://hcysun.me/vue-template-compiler-playground/)
+