Gemulation

Added:

• Upgrade system to the Gem Furnaces (you may have to break/replace the furnaces for them to update)
  • Three upgrade tokens to boost a furnace's speed, fuel efficiency, and fuel capacity.
  • Upgrades cannot be removed after installing unless you break the block.
• The potential for a JEI plugin if needed in the future

Changed:

• Balanced the furnace properties a bit better (there was an issue with how the fuel cost was calculated upon upgrading)