update README.md

Signed-off-by: Acmefocus <107723772@qq.com>

README.md

@@ -12,9 +12,9 @@ It is inspired by Tornado, Sinatra and Flask. beego has some Go-specific feature
 
     go get github.com/astaxie/beego
 
-#### Create hello directory 
+#### Create `hello` directory, cd `hello` directory
 
-   sudo mkdir hello
+   mkdir hello
    cd hello
  
 #### Init module