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.

MasterController.cpp

@@ -0,0 +1,27 @@
+#include "MasterController.h"
+#include "connectionmanagerwindow.h"
+#include "connectionlistmodel.h"
+
+
+MasterController::MasterController(QObject *parent) : QObject(parent)
+{}
+
+MasterController::~MasterController()
+{
+	delete m_connectionManagerWindow;
+	delete m_connectionListModel;
+}
+
+void MasterController::init()
+{
+	m_connectionListModel = new ConnectionListModel(this);
+
+	m_connectionManagerWindow = new ConnectionManagerWindow(this, nullptr);
+	m_connectionManagerWindow->show();
+
+}
+
+void MasterController::showConnectionManager()
+{
+	m_connectionManagerWindow->show();
+}