only try to set the srs if we have one
only try to set the srs if we have one

jwomeara/PDAL,DougFirErickson/PDAL,lucadelu/PDAL,DougFirErickson/PDAL,lucadelu/PDAL,Sciumo/PDAL,jwomeara/PDAL,radiantbluetechnologies/PDAL,radiantbluetechnologies/PDAL,verma/PDAL,verma/PDAL,lucadelu/PDAL,Sciumo/PDAL,boundlessgeo/PDAL,verma/PDAL,boundlessgeo/PDAL,mpgerlek/PDAL-old,jwomeara/PDAL,mtCarto/PDAL,mtCarto/PDAL,boundlessgeo/PDAL,mtCarto/PDAL,mpgerlek/PDAL-old,DougFirErickson/PDAL,mpgerlek/PDAL-old,mpgerlek/PDAL-old,DougFirErickson/PDAL,radiantbluetechnologies/PDAL,boundlessgeo/PDAL,Sciumo/PDAL,verma/PDAL,verma/PDAL,mtCarto/PDAL,lucadelu/PDAL,verma/PDAL,verma/PDAL,radiantbluetechnologies/PDAL,Sciumo/PDAL,jwomeara/PDAL