George Shakula issues

Results 7 issues of


                                            George Shakula

Fix building against monolithic USD

### PURPOSE Fix building against monolithic USD ### EFFECT OF CHANGE --

Crash on Windows with double 2080ti

Reported by @AlxndrTheWretch. I'm going to create a build that will use only the first GPU to make sure that this issue is multi-GPU related.

Denoiser gives unexpected result in dark areas

Input: ![inputColor](https://user-images.githubusercontent.com/22181845/71356215-31d55300-258a-11ea-8dc2-c205d039e183.png) Denoised: ![outputColor](https://user-images.githubusercontent.com/22181845/71356213-31d55300-258a-11ea-81aa-6351a538dfa3.png) ML team told me that this is a [known issue](https://amdrender.atlassian.net/browse/MR-18) and they are work on it

AspectRatioConformPolicy == adjustPixelAspectRatio is not supported

There is no such functionality in RPR that would allow us to set non-square pixels. Is there any way we could work around it?

Implement opacityThreshold support

Add support of instanceId and elementId AOV

Fix usage of displayColor primvar

Currently, `displayColor` is used as one color for whole mesh, but it should be used as attribute per vertex/face. Seems like RPR does not have such functionality, yet