corrected error message in port_scan and added check for user_excluded_ports
corrected error message in port_scan and added check for user_excluded_ports

pcahyna/leapp-to-prototype,GAZDOWN/prototype,vinzenz/prototype,vmindru/prototype,leapp-to/prototype,mfranczy/prototype,leapp-to/prototype,GAZDOWN/prototype,mfranczy/prototype,vmindru/prototype,ncoghlan/prototype,ncoghlan/prototype,vmindru/prototype,pcahyna/leapp-to-prototype,mfranczy/prototype,GAZDOWN/leapp,vinzenz/prototype,GAZDOWN/prototype,GAZDOWN/leapp,leapp-to/prototype,pcahyna/leapp-to-prototype,leapp-to/prototype,vinzenz/prototype,ncoghlan/prototype,GAZDOWN/prototype,vinzenz/prototype,vmindru/prototype,pcahyna/leapp-to-prototype,ncoghlan/prototype,mfranczy/prototype