Add API to control scaled health. Adds BUKKIT-4590
Add 1.6 PlaySound command. Fixes BUKKIT-4489
Add 1.6 SpreadPlayers command. Fixes BUKKIT-4508
Add 1.6 effect clear functionality. Fixes BUKKIT-4473
Account for relative coordinates in PlaySound. Fixes BUKKIT-4639
Add leash API.  Adds BUKKIT-4459 and BUKKIT-4583
Use player as point of reference for min volume. Fixes BUKKIT-4640

When the minimum volume is being used because the distance is over a
threshold, the unit vector delta should be added to the player's
location, instead of where the command specified location.

This change makes the player's location the point of reference for
playing sounds when distance to volume scale is lower than minimum
specified volume.
Pulling all pending Bukkit-JavaDoc changes
Pulling Bukkit into Bukkit-Javadoc