do a proper check to find out of PointSourceId dimension is available for #193
p2g writer
drivers.qfit.reader
Fix #194, default to specified offsets instead of throwing an exception when their reprojection fails
don't throw in filters.hexer's destructor
drivers.text.writer
Merge branch 'master' of github.com:PDAL/PDAL

Conflicts:
	doc/pipeline/index.txt