Add raw sound string playSound method. Adds BUKKIT-2443

A method has been added to Player which allows the server to send a sound string to the client. Assuming the client has the specified sound, it will be played. This is needed by the implementation of the /playsound command.
Revert to 1.5 despawning behaviour for Ocelots and Wolves. Fixes BUKKIT-4449
Add PathfinderGoalPanic for diff visibility.
Add timeout for Panic goal. Fixes BUKKIT-4531