Merge branch 'PointBuffer-constness' into yosemite-lint
added "-isystem /usr/local/include"

This should serve to shut up all the warnings from system headers (of
which the yosemite clang causes a zillion new ones in boost)
added common header to all unit test files
Merge pull request #529 from PDAL/yosemite-lint

Yosemite lint