add MovingLeastSquares access and Smooth kernel, disable normals for now (do we really need/use them?)
add pcl integration/todo notes
test without linking PCL in src/CMakeLists.txt, re-enable PCLBlockFilterTest and test for PCL presence using the StageFactory getFilterCreator
PCL unit tests pass with a warning if PCL plugins are not installed - though we should still move PCL tests to the plugin folder