Modern Beta for Forge 1.12.2

• Update none world spawner to release, to better reflect that it is the vanilla player spawn algorithm. A datafixer has been added to update worlds that use this particular setting.
• Fix several broken datafixers that broke worlds updating from old versions (1.4.0.0 and earlier) of this mod.
• Fix biome sampling bug in map previewer.

Technical

• Rewrite most of the datafixer code. Datafixers now only return the value to update a specific generator setting tag instead of operating on the entire ModernBetaGeneratorSettings factory object.
• Add new MOD_DATA_FIX registry to allow implementing datafixes using the new datafixer implementation.
• Deprecate original DATA_FIX registry.
• Add debug noise chunk source generator with debug preset. This can be toggled from the Debug section in the configuration.
• Update custom world presets to gracefully handle missing descriptions and/or icons.