Turbo for Distant Horizons

Added

• Distant terrain for Distant Horizons generated straight from the world noise, without generating chunks: many times faster than the Distant Horizons generator.
• Each terrain tile is generated on all worker threads at once.
• The game's own trees on detailed terrain near the player; species-shaped trees in distant forests.
• Snow, ice, bare rock on steep slopes, badlands terracotta bands and biome-specific seabeds in the distance.
• Distant terrain no longer vanishes for a moment while Distant Horizons switches it to more detail.
• Multiplayer: a server with this mod shares its world generation with players who have it, and their game generates the distant terrain itself, also on servers without Distant Horizons.
• Config: generator on/off, worker threads, full resolution, distant trees, real trees, sharing the world generation.