rem: void KMFilterActionIdentity::applyParamWidgetValue(QWidget* aParamWidget)
add: void KMFilterActionForward::applyParamWidgetValue(QWidget* aParamWidget)
context: void KMFilterActionIdentity::applyParamWidgetValue(QWidget* aParamWidget){  QComboBox* cbx = (QComboBox*)aParamWidget;  id = cbx->currentText();}