Add raw byte block state serialization

[TrollyLoki]

Adds two methods for (de)serialization of block states similar to the existing methods for (de)serialization of entities and item stacks.

I decided on serializing block states rather than blocks themselves because it allows plugins to examine the properties of deserialized data via the existing APIs before actually placing them in the world by using the update() method.

Example Usage:

private byte[] blockBytes;

@EventHandler
public void onBlockBreak(@NotNull BlockBreakEvent event) {
    // serialize block when it's broken
    BlockState state = event.getBlock().getState();
    blockBytes = Bukkit.getUnsafe().serializeBlock(state);
}

@EventHandler
public void onInteract(@NotNull PlayerInteractEvent event) {
    if (blockBytes == null)
        return;
    if (event.getAction() != Action.RIGHT_CLICK_BLOCK)
        return;
    if (event.getItem() == null || event.getItem().getType() != Material.BLAZE_ROD)
        return;

    // deserialize block at another location using a blaze rod
    Block block = event.getClickedBlock().getRelative(event.getBlockFace());
    BlockState state = Bukkit.getUnsafe().deserializeBlock(blockBytes, block);
    state.update(true);
}