Avoiding unnecessary overwrite of old image plane camera.
Avoiding unnecessary overwrite of old image plane camera.

When moving between orbit and walk mode and selecting the same camera twice the old image plane camera will get overwritten with the new one causing a duplicated image plane. This is avoided by comparing the image plane with the new camera object.

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