Kappa Shader v3.1 Preview T1

Not a lot of changes since the last preview, but for the sake of convenience here is the full changelog since 3.0a:

- added cloud shadows
- color and grading adjustments
- improved RSM antibleeding
- added various new settings
- improved SSRT
- fixed ssrt emission in nether
- adjusted emission and blocklight brightness
- added anamorph lens support on DoF and lens flares
- improved water waves
- fixed missing labPBR emission in nether (T1a)