MicroSplat - HDRP 2020 Support v3.9.2

Adds support for Unity's High Definition Render Pipeline (HDRP) to MicroSplat

Unity's new Scriptable Render Pipeline (SRP) requires a full rewrite of all shaders for each version of each SRP. This module adds support for targeting the High Definition Render Pipeline shipping with Unity 2020.3LTS.

Tested with 2020.3LTS w/ HDRP 10.x

The following features are not currently supported

- Render Baking

Asset version: 3.9.2