Added command /tchest forget [player] (while looking at chest)
Added command /tchest forget -allplayers (while looking at chest)
Added a check to the set command. If use set command on existing treasure chest. Item list is updated. (fixes ghost items)
Now using SQLite (doesn't require any installation) You can delete the file plugins/TreasureChest/players.yml Keep in mind that the plugin will forget that any player found any chest.