Armor Expansion

Refactored ModItems to initialise items when declaring them. Reduces unneccessary extra lines.
Armor model rendering is now handled by the material, not the armor class.
Changed null check of onArmorTick to check stack, as getting item from the ItemStackFromSlot causes a nullpointer exception
Tidied up addition and removal of enchantments on Lapis Armor
Updated item model JSONs from builtin/generated to item/generated and item/handheld for items and tools.