Ref T225, force stylesheet in CForm base class and used by all forms

* Allows to use stylesheet attributes like [readonly]
* changing to "readonly" applies correct stylesheet

src/blackgui/editors/situationform.cpp

@@ -113,6 +113,7 @@ namespace BlackGui
         void CSituationForm::setReadOnly(bool readonly)
         {
             ui->comp_Coordinate->setReadOnly(readonly);
+            this->forceStyleSheetUpdate();
         }
 
         void CSituationForm::setSelectOnly()