adding proxy models and search to all sql models

src/cpp/presentationsqlmodel.h

@@ -2,6 +2,7 @@
 #define PRESENTATIONSQLMODEL_H
 
 #include <QSqlTableModel>
+#include <QSortFilterProxyModel>
 #include <qobject.h>
 #include <qobjectdefs.h>
 #include <qqml.h>
@@ -52,4 +53,14 @@ private:
     int m_pageCount;
 };
 
+class PresentationProxyModel : public QSortFilterProxyModel
+{
+  Q_OBJECT
+
+public:
+  explicit PresentationProxyModel(QObject *parent = nullptr);
+  
+  
+};
+
 #endif //PRESENTATIONSQLMODEL_H