Setup rtabmap working directory on launch (so delete action works on startup even if the working directory is not the default one)

git-svn-id: http://rtabmap.googlecode.com/svn/trunk/rtabmap@293 f169173b-cf89-36c8-b27e-44dbe73f0c83

guilib/include/rtabmap/gui/MainWindow.h

@@ -73,6 +73,8 @@ public:
 	MainWindow(PreferencesDialog * prefDialog = 0, QWidget * parent = 0);
 	~MainWindow();
 
+	QString getWorkingDirectory() const;
+
 public slots:
 	void changeState(MainWindow::State state);