Minecraft wiki entry for Flattening, associated text: Damage in the root of the item data removed.
Damage added in the tag tag, only used for durability.
map integer added in the tag tag, for maps.
Base of Shields has the colors in the opposite order for consistency.
ench for enchantments got renamed to Enchantments.
Enchantment Ids in Enchantments and StoredEnchantments now use the string ids.