dispose method
void
dispose()
Dispose the class when finished using it
Implementation
void dispose() {
_processedFeaturesController.close();
_processedPointsController.close();
_processedMultipointsController.close();
_processedLinesController.close();
_processedMultilinesController.close();
_processedPolygonsController.close();
_processedMultipointsController.close();
_endSignalController.close();
}