Minor fix :
- Remove usage of System.out.println, that leads to a warning on server launch

Update :
- If a player have the permission nomending.bypass, he can bypass all of the plugin's restriction (i know, when you want to disable mending, it's for all of the users, but i think some people will still find some use to it !)
NB: the bypass is valid both for pickup AND usage. If a player without bypass take a mending book from an other player (obtained with bypass), he can equip it to his items, but if "enable-mending: false", it will disapear when repaired ! (if the player with bypass use it, it not disapear).