blindly cast to char* for unix putenv
blindly cast to char* for unix putenv

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