fixed traceback when using python api to evaluate oval
fixed traceback when using python api to evaluate oval

was getting traceback "TypeError: 'OVAL_Class' object does not support indexing"
looks like method of output callback registration was changed, but agent_eval_system was not synced

jan-cerny/openscap,OpenSCAP/openscap,ybznek/openscap,redhatrises/openscap,postfix/openscap,OpenSCAP/openscap,redhatrises/openscap,postfix/openscap,postfix/openscap,openprivacy/openscap,Hexadorsimal/openscap,openprivacy/openscap,isimluk/openscap,redhatrises/openscap,openprivacy/openscap,postfix/openscap,isimluk/openscap,openprivacy/openscap,ybznek/openscap,Hexadorsimal/openscap,ybznek/openscap,redhatrises/openscap,ybznek/openscap,mpreisler/openscap,redhatrises/openscap,isimluk/openscap,mpreisler/openscap,OpenSCAP/openscap,OpenSCAP/openscap,isimluk/openscap,OpenSCAP/openscap,jan-cerny/openscap,openprivacy/openscap,jan-cerny/openscap,Hexadorsimal/openscap,isimluk/openscap,mpreisler/openscap,ybznek/openscap,mpreisler/openscap,isimluk/openscap,mpreisler/openscap,jan-cerny/openscap,jan-cerny/openscap,Hexadorsimal/openscap,jan-cerny/openscap,postfix/openscap,redhatrises/openscap,mpreisler/openscap,OpenSCAP/openscap,Hexadorsimal/openscap,ybznek/openscap,postfix/openscap,openprivacy/openscap,Hexadorsimal/openscap