Block: Clean up internal constructor inconsistencies

I don't dare look how big this commit is or how many bugs it introduced...

src/pocketmine/block/DiamondOre.php

@@ -30,20 +30,10 @@ use function mt_rand;
 
 class DiamondOre extends Solid{
 
-	protected $id = self::DIAMOND_ORE;
-
-	public function __construct(){
-
-	}
-
 	public function getHardness() : float{
 		return 3;
 	}
 
-	public function getName() : string{
-		return "Diamond Ore";
-	}
-
 	public function getToolType() : int{
 		return BlockToolType::TYPE_PICKAXE;
 	}