update doc, polish #976

site/src/site/sphinx/advanced-use.md

@@ -7,6 +7,7 @@
 * help——查看命令帮助信息
 * [cat](cat.md)——打印文件内容，和linux里的cat命令类似
 * [grep](grep.md)——匹配查找，和linux里的grep命令类似
+* [tee](tee.md)——复制标准输入到标准输出和指定的文件，和linux里的tee命令类似
 * [pwd](pwd.md)——返回当前的工作目录，和linux命令类似
 * cls——清空当前屏幕区域
 * session——查看当前会话的信息

site/src/site/sphinx/commands.md

@@ -33,6 +33,7 @@
 
 * [cat](cat.md)
 * [grep](grep.md)
+* [tee](tee.md)
 * [pwd](pwd.md)
 * [options](options.md)
 

site/src/site/sphinx/en/advanced-use.md

@@ -7,6 +7,7 @@ Advanced Usage
 * cls - clear the screen
 * [cat](cat.md) - Concatenate and print files
 * [grep](grep.md) - Pattern searcher
+* [tee](tee.md) - Copies standard input to standard output, making a copy in zero or more files.
 * [pwd](pwd.md) - Return working directory name
 * session - display current session information
 * [reset](reset.md) - reset all the enhanced classes. All enhanced classes will also be reset when Arthas server is closed by `stop/shutdown`

site/src/site/sphinx/en/commands.md

@@ -33,6 +33,7 @@ All Commands
 
 * [cat](cat.md)
 * [grep](grep.md)
+* [tee](tee.md)
 * [pwd](pwd.md)
 * [options](options.md)