[zh_CN zh/development/rest.rst: correct language in meta tags

Author: blackpuppy

zh/development/rest.rst

@@ -209,5 +209,5 @@ CakePHP 中，:php:class:`RequestHandlerComponent` 有助于实现这一点。
 
 
 .. meta::
- :title lang=en: REST
- :keywords lang=en: application programmers,default routes,core functionality,result format,mashups,recipe database,request method,easy access,config,soap,recipes,logic,audience,cakephp,running,api
+ :title lang=zh_CN: REST
+ :keywords lang=zh_CN: application programmers,default routes,core functionality,result format,mashups,recipe database,request method,easy access,config,soap,recipes,logic,audience,cakephp,running,api