updated centinel.py to make the subparsers work
updated centinel.py to make the subparsers work

iclab/centinel,ben-jones/centinel,JASONews/centinel,lianke123321/centinel,iclab/centinel,rpanah/centinel,lianke123321/centinel,Ashish1805/centinel,rpanah/centinel,iclab/centinel,lianke123321/centinel,rpanah/centinel