move more stuff into common.hpp
move more stuff into common.hpp

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