docs: document global components

Author: ulivz

docs/guide/markdown.md

@@ -268,7 +268,7 @@ module.exports = {
   }
 </style>
 
-## Import Code Snippets <Badge text="Experimental" type="warn"/> <Badge text="0.10.1+" type="tip"/>
+## Import Code Snippets <Badge text="beta" type="warn"/> <Badge text="0.10.1+" type="tip"/>
 
 You can import code snippets from existing files via following syntax:
 

docs/guide/using-vue.md

@@ -175,3 +175,48 @@ export default {
   }
 }
 </script>
+
+## Built-In Components
+
+### OutboundLink <Badge text="stable"/>
+
+It(<OutboundLink/>) is used to indicate that this is an external link, and VuePress has added this component to each external link.
+
+### ClientOnly <Badge text="stable"/>
+
+See [Browser API Access Restrictions](#browser-api-access-restrictions).
+
+### Content <Badge text="beta" type="warn"/>
+
+- **Props**:
+
+  - `custom` - boolean
+
+- **Usage**：   
+   
+The compiled content of the current `.md` file being rendered. This will be very useful when you use [Custom Layout](../default-theme-config/README.md#custom-layout-for-specific-pages).
+
+``` vue
+<Content/>
+```
+
+**Also see:** 
+
+- [Custom Themes > Content Outlet](./custom-themes.md#content-outlet)
+
+  
+### Badge <Badge text="beta" type="warn"/> <Badge text="0.10.1+"/>
+
+- **Props**:
+
+   - `text` - string
+   - `type` - string, optional value: `"tip"|"warn"|"error"`, defaults to `"tip"`.
+   - `vertical` - string, optional value: `"top"|"middle"`, defaults to `"top"`.
+
+- **Usage**:
+
+You can use this component at the end of header text to add some status for some API:
+   
+``` md
+### Badge <Badge text="beta" type="warn"/> <Badge text="0.10.1+"/>
+```   

docs/zh/guide/markdown.md

@@ -266,7 +266,7 @@ module.exports = {
   }
 </style>
 
-## 导入代码段 <Badge text="Experimental" type="warn"/> <Badge text="0.10.1+" type="tip"/>
+## 导入代码段 <Badge text="beta" type="warn"/> <Badge text="0.10.1+" type="tip"/>
 
 你可以通过下述的语法导入已经存在的文件中的代码段：