add operator < and > for sorting
add operator < and > for sorting

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