modify delivery status interface
modify version info in enc/dec
Merge pull request #1333 from huili2/print_ver_master

modify version info in enc/dec
fix pps caused death loop issue
Merge pull request #1330 from ruil2/delivery_status

modify delivery status interface
Merge pull request #1335 from lyao2/fixppsbug

fix pps caused death loop issue
Merge remote-tracking branch 'upstream/master' into travis.osx