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/Melon.php

@@ -29,16 +29,6 @@ use function mt_rand;
 
 class Melon extends Transparent{
 
-	protected $id = self::MELON_BLOCK;
-
-	public function __construct(){
-
-	}
-
-	public function getName() : string{
-		return "Melon Block";
-	}
-
 	public function getHardness() : float{
 		return 1;
 	}