Moved some util3d methods to Transform.h, Graph.h and Compression.h

Added computePath() method implementating A star on graph
GUI: SetWindowModified() and user should explicitly save the GUI config to keep them
Calibration: added mirror checkbox, added device id argument

guilib/include/rtabmap/gui/ImageView.h

@@ -75,6 +75,9 @@ public:
 	void clearLines();
 	void clear();
 
+signals:
+	void configChanged();
+
 protected:
 	virtual void contextMenuEvent(QContextMenuEvent * e);
 	virtual void wheelEvent(QWheelEvent * e);