Just Enough Items (JEI)

Fix #766 Crash when looking at broken Anvil recipe

Add API for handling cheating in custom ingredients

#764 Add earlier checks for empty ItemStacks

Use icons for button labels instead of text (better for unicode)

Move recipe category tab arrows up to their own buttons (show more tabs)

Prioritize lookups to show categories handled by the currently-open gui

Make all ingredients in a recipe cycle with the same offset

Add ingredient lookup memory to remember where players were last looking

Cleanup