Item models should work now

[TehNut]

• Fixes buildscript issue (compiole -> compile)
• Item models should work now
• Adds new model registration system
  • IVariantProvider
  • Only for inventory models. Does nothing for in world.
  • Current implementation is only usable in the Core module. Wasn't sure how you want to do it for all modules.
  • Works for both blocks and items.
  • If the name isn't inventory, it will look for a valid variant in modid:blockstates/items/NAME.json. Otherwise, it'll use a standard item model json.
• Added a new ItemEnum class
  • Useful for having sub-items without worrying about handling meta.

[LordFokas]

Thanks a lot :)