rem: void save( QCheckBox * b, KConfigBase & c, const BoolConfigEntry & e ) {
add: void save( QButtonGroup * g, KConfigBase & c, const EnumConfigEntry & e ) {
context:   void save( QCheckBox * b, KConfigBase & c, const BoolConfigEntry & e ) {    Q_ASSERT( c.group() == e.group );    c.writeEntry( e.key, b->isChecked() );  }