Revert "Block: Get rid of state bitmasks"

This reverts commit b7b05e729e.

Apparently this was premature, because we still need these things to deal with default state remapping.

src/pocketmine/block/NetherReactor.php

@@ -44,6 +44,10 @@ class NetherReactor extends Solid{
 		$this->state = BlockDataValidator::readBoundedInt("state", $stateMeta, 0, 2);
 	}
 
+	public function getStateBitmask() : int{
+		return 0b11;
+	}
+
 	public function getToolType() : int{
 		return BlockToolType::TYPE_PICKAXE;
 	}