add description of header usage.

README.md

@@ -150,10 +150,11 @@ When you need to use smart-doc to generate more API document information, you ca
   }],
   "requestHeaders": [// Set global request headers, no need to set
     {
-      "name": "token",
-      "type": "string",
-      "desc": "desc",
+      "name": "token",//header name
+      "type": "string",//header type
+      "desc": "description of this header.",
       "required": false,
+                        "value":"your header value",
       "since": "-"
     }
   ]

README_CN.md

@@ -136,11 +136,12 @@ smart-doc官方目前已经开发完成[maven插件](https://gitee.com/smart-doc
   ],
   "requestHeaders": [ //设置请求头，没有需求可以不设置
     {
-      "name": "token",
-      "type": "string",
-      "desc": "desc",
-      "required": false,
-      "since": "-"
+      "name": "token",//请求头名称
+      "type": "string",//请求头类型
+      "desc": "desc",//请求头描述信息
+      "value":"token请求头的值",//不设置默认null
+      "required": false,//是否必须
+      "since": "-"//什么版本添加的改请求头
     }
   ],
   "rpcApiDependencies":[{ // 项目开放的dubbo api接口模块依赖，配置后输出到文档方便使用者集成