Merge pull request #146 from acstache/bleeding

Implement boss health using the Bukkit Max Health API, and remove health-multiplier limitation of "0 < limit <= 1".
Merge pull request #149 from acstache/bleeding

braaaaaaains... just kidding, but here are some more zombies
Better multiworld support.
Simple attempt at anti-flying.
Add Metrics to shut slipcor up!
Update plugin.yml
Break or die!