We know these updates (can) break plugins bypassing Bukkit. They are needed for
smooth updates however. There will be another one right before before 1.1-R1.
We also teach CraftWorld how to explode an event, taken from
Explosion.a(boolean) (the code that breaks blocks and drops them on the ground).
The EnderDragon has a flag that slows it down when it hits unbreakable blocks:
Obsidian, White Stone or Bedrock. It might be useful to extend the event so that
plugins can set this.
Letting the API set the default yield for an explosion event has been
deprecated, so we now set the default yield using the appropriate constructor.
