OpenVDB 3.0 beta
Visual C++ fixes
updated NodeManager
Merge changes from Houdini trunk. Notable changes:

- (openvdb_houdini/Makefile) Fix bash error when HCUSTOM_EXPORT is empty
- (GEO_PrimVDB) Voxel evaluation now also handles bool grids
- (GEO_PrimVDB) Copy visualization options
- (GU_PrimVDB) Fix crash when saving NULL string attribute values to .vdb
- (Various) Save .vdb with blosc enabled unless HOUDINI13_VOLUME_COMPATIBILITY
  is set.
- (Various) Load .vdb with delay loading always set to false
- (Various) Add missing "include what you use" headers
- (GeometryUtil) Add missing node interest in frustumTransformFromCamera()
- (ParmFactory and SOPs) Group parameters now have a selection button that
  allows one to use it for reselecting in the viewport.

Conflicts:

	openvdb_houdini/houdini/GEO_PrimVDB.cc
Merge pull request #27 from sideeffects/send_upstream

Merge changes from Houdini trunk. Notable changes:
Various fixes
bug fixes
bug fix in NodeManager
various fixes
GLFW 3 support and point partitioning improvements
Fixed a bug in Tree::ValueOffIter and added utility methods for point partitioning in Houdini.
Fixed a bug in Tree::ValueOffIter and added utility methods for point partitioning in Houdini.
Fixed a bug in Tree::ValueOffIter and added utility methods for point partitioning in Houdini.
Move PointIndexGrid tools into GU_VDBPointTools

Conflicts:

	openvdb_houdini/houdini/geometry.h
SESI_OPENVDB also might not have OPENVDB_HOUDINI_API
Override updateParmsFlags() in Morph Level Set
Merge pull request #30 from sideeffects/send_upstream

New changes from Houdini trunk (GU_VDBPointTools)
various improvements
fixed mesh simplification bug
Blosc compression