Better Shulker Boxes 3.0.0 [PRE-RELEASE]

I rewrote the plugin from scratch, the only things from the old version that I did not port are the worldguard flag and the right-click on a shulker inside a chest feature. This version should work without issues for any version between 1.13 and 1.18, both spigot and paperspigot.

The JAR will not be published in Spigot until I make sure everything works fine, for the moment you can download it from here.