Version 3.0

• Removed the update/task system. If you need one just use the onOpen and onClose to create a similar one like this

  BukkitTask task = getServer().getScheduler().runTaskTimer(this, () -> {}, 10, 10);
  inv.addCloseHandler(e -> task.cancel());

• Removed the 'builder' style: methods like addItem now return void (more lines will keep your code cleaner and will not kill you)
• Split the FastInv class in 2 class (3 with the ItemBuilder)
• Remove the async support, if you need it you can really easily do one yourself (this prevent the creation of Runnable everywhere)
• Renamed most of the methods to match Bukkit names
• Removed the FastInv events, now it just use the Bukkit events
• Add removeItem(int slot) and removeItems(int... slots), it's cleaner than adding a null item
• Improved ItemBuilder
• If you have any problem with this new version you can contact me on my Discord server