Adding shortest path line geometry.
Adding shortest path line geometry.

Adding journey wrapper functionality to create a line geometry for showing the shortest path in flying mode. Adding public methods for showing and hiding shortest path.

oscarlorentzon/OpenSfM,mapillary/OpenSfM,mapillary/OpenSfM,sunbingfengPI/OpenSFM_Test,oscarlorentzon/OpenSfM,edgarriba/OpenSfM,BrookRoberts/OpenSfM,sunbingfengPI/OpenSFM_Test,edgarriba/OpenSfM,NicWayand/OpenSfM,oscarlorentzon/OpenSfM,NicWayand/OpenSfM,mapillary/OpenSfM,onecue/OpenSfM,sunbingfengPI/OpenSFM_Test,edgarriba/OpenSfM,BrookRoberts/OpenSfM,BrookRoberts/OpenSfM,oscarlorentzon/OpenSfM,edgarriba/OpenSfM,onecue/OpenSfM,mapillary/OpenSfM,BrookRoberts/OpenSfM,BrookRoberts/OpenSfM,oscarlorentzon/OpenSfM,edgarriba/OpenSfM,NicWayand/OpenSfM,NicWayand/OpenSfM,onecue/OpenSfM,sunbingfengPI/OpenSFM_Test,onecue/OpenSfM,sunbingfengPI/OpenSFM_Test,mapillary/OpenSfM,onecue/OpenSfM,NicWayand/OpenSfM