[ENHANCEMENT] Scripting system for mobs

[SirFancyBacon]

Objective:

implement a scripting system similar to CustomNPCs.

Purpose:
Brawlator is the first custom mobs plugin for sponge that i am aware of; adding CustomNPC-like features could possible draw many folks over to the Sponge community helping to draw new devs to further improve Sponge.

Example of CustomNPC scripting API
http://www.kodevelopment.nl/minecraft/customnpcs/scripting

Key events:
the first events the team should focus on implementing are:

damaged()
died()
attack()
tick()
timer()

this should provide most of the functionality i think most people desire in a mob scripting system.
Eventually we should find a way to implement ranged attacks and melee attacks on the same mob; then split attack() into meleeAttack() and rangedAttack()

Two other very useful features would be:
target()
targetLost()

This would help in the creation of Finite State Machines and the first step into custom AI for Brawlator.

Additional notes:
CustomNPCs has a Javascript engine spawned for each NPC. this allows you to use the same code without interfering with any global effects; I think Brawlator should follow suit for the same reason.

As such if we needed to pass events between scripting engines; two functions would be needed setTempData() and getTempData()