Add Send sms observer to monitor sms sending successfully
Note:
    1. The monitor server is lunched when system boots
    2. Through the monitor server is lunched when system boots, the system
    may kill this server in many situations(for example: under sleep
    mode). So we can not be ensure that every sms sent will be monitored,
    but we should try my best to meet the monitor requirement, I re-start
    this monitor server when the system receives a sms.