Tool: cleanup durability handling, closes #379

long overdue... this isn't quite as extensible as the original api3/blocks system was, but this is primarily intended to replace Item->useOn(). If plugins want to use it it can be extended later on.

src/pocketmine/item/Hoe.php

@@ -23,10 +23,15 @@ declare(strict_types=1);
 
 namespace pocketmine\item;
 
+use pocketmine\entity\Entity;
+
 class Hoe extends TieredTool{
 
 	public function isHoe(){
 		return $this->tier;
 	}
 
+	public function onAttackEntity(Entity $victim) : bool{
+		return $this->applyDamage(1);
+	}
 }