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/form.cpp

@@ -8,6 +8,7 @@
  */
 
 #include "blackgui/editors/form.h"
+#include "blackgui/guiutility.h"
 #include <QApplication>
 #include <QClipboard>
 #include <QShortcut>
@@ -48,6 +49,11 @@ namespace BlackGui
             this->jsonPasted(data);
         }
 
+        void CForm::forceStyleSheetUpdate()
+        {
+            CGuiUtility::forceStyleSheetUpdate(this);
+        }
+
         CFormDbUser::CFormDbUser(QWidget *parent) : CForm(parent)
         { }