parse_CAs.py - add few comments
parse_CAs.py - add few comments

PeterMosmans/cipherscan,MikeDawg/cipherscan,jvehent/cipherscan,jvehent/cipherscan,jvehent/cipherscan,MikeDawg/cipherscan,PeterMosmans/cipherscan,MikeDawg/cipherscan,PeterMosmans/cipherscan