fix: allow use of OpenCV 3 (imgcodecs) or below < 3 (FindOpenCV requires all OPTIONAL_COMPONENTS)
fix: allow use of OpenCV 3 (imgcodecs) or below < 3 (FindOpenCV requires all OPTIONAL_COMPONENTS)

mapillary/OpenSfM,oscarlorentzon/OpenSfM,oscarlorentzon/OpenSfM,mapillary/OpenSfM,oscarlorentzon/OpenSfM,mapillary/OpenSfM,mapillary/OpenSfM,mapillary/OpenSfM,oscarlorentzon/OpenSfM,oscarlorentzon/OpenSfM