Fix the PrefHandler::_ConfirmFont to take into account not only the
font family but the font style too. This improves the popup menu
checkmark synchronization in the Preferences View. This problem can
be reproduced on very first start of application without previously
stored Terminal settings. Default family/style for this case is
currently defined as "Courier 19BT"/"Regular" but default fixed
font has correspondently "DejaVu Sans Mono"/"Book". Previous version
of _ConfirmFont() process only the family and left the style in default
"Regular" one. So opening Preferences View and attempting to set the
checkmark on corresponding family/style menuitem was usually failed.
ef60154123