Easy Shop Mod Improved

Forked version of the Easy Shop Mod by Mohamed-SGG53.

All credit to original mod and creator here.

My edits:

• Each player can now create two shops; one for selling items, one for buying items
• Shops have a sell mode where players can hand over items and receive payment
• Shop trades can be linked to a chest; the chest is the stock source, and the trade automatically disappears from the shop when the chest runs empty, then reappears when you refill it
• NPC names are customizable; no longer locked to "[Your Name]'s Shop"
• The skin file notification only appears when you create a shop, not for every player on login