Integration of the path planner into rtabmap's memory management to actually retrieve nodes on the planned path on the graph.

Added Rtabmap::clearPath(), Rtabmap::computePath(), Rtabmap::getPathGoalId() and Rtabmap::updateGoalIndex() methods.
Added virtual links when path retrieval is activated (virtual links are not saved to database and removed when the path goal is reached).
New parameters: RGBD/GoalReachedRadius and RGBD/MaxAnticipatedNodes
Refactored how loop closure hypotheses are selected (fixed ratio between consecutive hypotheses, not the last loop closure).
Updated getNodesInRadius() to use all filtered scans.
GUI: window can be saved/loaded maximized
GUI: saving Graph View parameters to config.ini

guilib/src/CMakeLists.txt

@@ -22,6 +22,7 @@ SET(headers_ui
 	./PostProcessingDialog.h
 	./ExportCloudsDialog.h
 	./MapVisibilityWidget.h
+	./GraphViewer.h
 )
 
 SET(uis