实现监视进程的看门狗程序，可以监听到进程是否存在，并作相应处理。

实现监视进程的看门狗程序，可以监听到进程是否存在，并作相应处理。-Realize the watchdog process to monitor the process, you can listen to the process of existence, and the corresponding treatment.

ProcessWatcher that watch when process are created or destroied or modified