add empty() method to check if a GDAL srs doesn't have anything
add empty() method to check if a GDAL srs doesn't have anything

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