Added Windows/Linux builds of OpenVDB

...along with support boost libaries and whatnot. With this update,
Nuparu's version number is incrementing to v0.2.18.6a, and all core
libraries now have full macOS/Windows/Linux support.

Author: betajippity

README.md

@@ -1,7 +1,7 @@
 Nuparu
 ======
 
-v0.1.17.32a
+v0.2.18.6a
 
 Third Party dependencies and foundation libraries for Karl's graphics projects
 
@@ -27,9 +27,9 @@ Updated:
 * [tinyformat](https://github.com/c42f/tinyformat) 2.1.0 (Src)
 * [Zlib](https://www.zlib.net) 1.2.11 (Win/Linux)
 * [TBB](https://www.threadingbuildingblocks.org/) 2018 Update 2 (Mac/Win/Linux)
-* [Boost](http://www.boost.org) 1.66.0 (Mac)
+* [Boost](http://www.boost.org) 1.66.0 (Mac/Win/Linux)
 * [OpenSubdiv](http://graphics.pixar.com/opensubdiv/docs/intro.html)  3.3.1 (Mac/Win/Linux)
-* [OpenVDB](http://www.openvdb.org/) 5.0.0 (Mac)
+* [OpenVDB](http://www.openvdb.org/) 5.0.0 (Mac/Win/Linux)
 
 Notes: