Visual: Armor Trims

This release removes the custom armor trim cutout due to this bug being fixed. This means that Visual: Armor Trims should now work much better with other resource packs, as long as they don't change the armor shape.

Changes

• Remove assets/minecraft/textures/item/<item_name>/{base, overlay} directories and their contents.
• Simplify all assets/minecraft/models/item/<item_name>/minecraft/<trim_name>.json, they no longer override layer0 and instead delegate to the vanilla model.
• Leather armor now has the overlay on layer1 and the trim on layer2.