[idd] helper/CEditWidget: support enable/disabling edit controls

idd/LGIddHelper/CEditWidget.h

@@ -9,6 +9,8 @@ public:
   std::wstring getValue();
   int getNumericValue();
 
+  bool enable(bool enabled = true);
+  bool disable() { return enable(false); }
   void setValue(const std::wstring &value);
   void setNumericValue(int value);
 };