Add Distant Horizons support.

[bearfm]

https://gitlab.com/jeseibel/distant-horizons

[EsserGaming]

Yo, I noticed some issues with the fog and the clouds. It seems to overwrite the fog settings.

Shaders on.

Shaders off.

[EsserGaming]

I found some logs that may be useful.

[22:27:32] [Render thread/ERROR]: Unexpected; somehow the Opaque + Translucent pass ran with shaders on.
[22:27:32] [Render thread/WARN]: Shader clouds could not find uniform named ModelViewMat in the specified shader program.
[22:27:32] [Render thread/WARN]: Shader clouds could not find uniform named ProjMat in the specified shader program.
[22:27:32] [Render thread/WARN]: Shader clouds could not find uniform named ColorModulator in the specified shader program.
[22:27:32] [Render thread/WARN]: Shader clouds could not find uniform named FogStart in the specified shader program.
[22:27:32] [Render thread/WARN]: Shader clouds could not find uniform named FogEnd in the specified shader program.
[22:27:32] [Render thread/WARN]: Shader clouds could not find uniform named FogColor in the specified shader program.

[bearfm]

damn