ui: graph view edges

Added simple edges to the graph view. Also fixed a memory leak source in QtMainWindow.

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src/app/qt/view/graphElements/QtGraphEdge.h

@@ -0,0 +1,28 @@
+#ifndef QT_GRAPH_EDGE_H
+#define QT_GRAPH_EDGE_H
+
+#include <memory>
+
+#include "qgraphicsitem.h"
+
+#include "component/view/graphElements/GraphEdge.h"
+
+class GraphNode;
+
+class QtGraphEdge:
+	public GraphEdge,
+	public QGraphicsLineItem
+{
+public:
+	QtGraphEdge(const std::weak_ptr<GraphNode>& owner, const std::weak_ptr<GraphNode>& target);
+	virtual ~QtGraphEdge();
+
+	virtual void ownerMoved();
+	virtual void targetMoved();
+
+private:
+	std::weak_ptr<GraphNode> m_owner;
+	std::weak_ptr<GraphNode> m_target;
+};
+
+#endif // QT_GRAPH_EDGE_H