Better Iron Recycling

• Split pack into two versions: one for 1.21.x and one for 1.20.x
• Added new items for smelting recipes:
  • Minecarts with hoppers can now be smelted/blasted into iron blocks
  • Flint and steel and crossbows can now be smelted into iron nuggets
  • Smithing tables can now be smelted into iron ingots
• Added recycling recipes via stonecutter
• Blast furnace, stonecutter, pistons and sticky pistons can be recycled into varying amounts of iron nuggets

This is likely the final update for 1.20-1.20.6, barring bug fixes or brilliant ideas.