add the function of connection on demand,add fastdfs module

1. add the function of connection on demand
2. add thread to check kup device server receving video strem service
3. add fastdfs module and correct spell errors
add kainode exceptional cases events,update DeviceCommsAPI.thrift

1.add kup stream poor, uploading stream failure, kainode registered and unregisterd events
2.update DeviceCommsAPI.thrift getDevices(), and device server side
  return json formated information of the devices, including device id and
  cloud recording enabled status