Replaces PR #1185 for 1.13 Add some new cancellable enderdragon events dealing with its fireball shooting and the areaeffectcloud it spawns. Based on [talking with someone with a specific use-case](https://www.spigotmc.org/threads/cancel-projectilehitevent.326466/) this was [confirmed to work](http://i.imgur.com/ezlfpKC.png) for them in PM.