Release 40

添加一些clr实现的基本命令

```
clr_pwd                    - print current directory by clr
clr_ls {directory}         - list files by clr
clr_cd {directory}         - change directory by clr
clr_ps                     - list process by clr
clr_netstat                - netstat by clr
clr_ping {host}            - ping by clr
clr_cat {file}             - view file contents by clr
clr_rm {file}              - delete file by clr
```