Update Greyhound driver.
Merge pull request #448 from PDAL/noiter

Remove iterators from pdal readers
NumRead was wrong
Update overview for readers.
Add missing image.
Merge branch 'master' of https://github.com/PDAL/PDAL
Add tree depth query to QuadIndex.
Reorganize test data #441
Fix RST.
Explicitly turn off rivlib in Travis

The libraries aren't available for open download, so I'm not sure if its
worth the hassle to set up the tests on Travis.
Add minimal option
Merge branch 'master' into rxp-driver

Conflicts:
	src/StageFactory.cpp
Remove superflous method
Merge branch 'rxp-driver' into rxp-driver-inclination-correction

Conflicts:
	include/pdal/drivers/rxp/RxpReader.hpp
	src/drivers/rxp/RxpReader.cpp
More work for merging