Introduced the MasterController as part of working on loading catalogue information.

Need a central piece to manage the catalogue data per database to prevent loading
this multiple times. MasterController is now also used to enable reopening the
connection manager from a query window after the connection manager has been closed.

typeselectionitemmodel.h

@@ -0,0 +1,21 @@
+#ifndef TYPESELECTIONITEMMODEL_H
+#define TYPESELECTIONITEMMODEL_H
+
+#include <QAbstractListModel>
+
+class TypeSelectionItemModel : public QAbstractListModel
+{
+	Q_OBJECT
+
+public:
+	explicit TypeSelectionItemModel(QObject *parent = 0);
+
+
+	int rowCount(const QModelIndex &parent = QModelIndex()) const override;
+	int columnCount(const QModelIndex &parent = QModelIndex()) const override;
+	QVariant data(const QModelIndex &index, int role = Qt::DisplayRole) const override;
+
+private:
+};
+
+#endif // TYPESELECTIONITEMMODEL_H