Add functionality to fake blockId for shaders

[DarkShadow44]

My version of overriding blockids for shaders, to allow each quad to have their own effect.
Should be compatible with all shaders that us the optifine blockId logic to select materials. For example needed for LittleTiles, to have multiple different effects inside a block.

Also see

• The needed GTNH Lib change: Add functionality to fake blockId for shaders GTNHLib#114
• The LittleTiles example that uses this: DarkShadow44/LittleTiles@acac13a

Alternative to #869, posted here for better visibility, testing and review.