USD, Render Manager, Keyframe Animation in LibThree beta 8

Huge update this time!

The Universal Scene Description (USD) file format is now supported. There are still few missing features like import of skeletal animation and lights.

Intel's Open Image Denoiser is now supported as an alternative to the Optix and the built-in denoiser.  It supports any x64 processor and performs really well.

It's finally possible to create  and edit keyframe animations inside LibThree.  Any property can be driven by Bezier or Catmull-Rom time curves.

New tools were added in order to easy the rendering of animation sequences on multiple machines.

For the full changelog, check out http://libthree.com/change_logs.html