Update options information for LAS writer
Fix for #142, actually use the z_offset reference if requested
Predicate and programmable filters
Merge branch 'master' of github.com:PDAL/PDAL into pipelinedocs
Merge branch 'master' of github.com:PDAL/PDAL
declare buffer as const
Merge branch 'master' of github.com:PDAL/PDAL into pipelinedocs