Added support for potions to rank cost
Added support for damageable items. i.e. can no longer turn in damaged items for rank up
Fixed NPC listener null error
Fixed PassiveGUI and PassiveNPC permission node
Fixed Rank and RankManager null errors
Fixed available rank checks to check LuckPerm group

Example config for potions:

Potion Item ID : amount required
splash_potion{Potion:strong_healing}:1

Item IDs can be found at https://minecraftitemids.com/