Inter-Mod Communication stuff

[cosmicdan]

So here's that thing I was going to do. Works perfectly for our purposes, but let me know if there's something you want done differently.

[cosmicdan]

Oh, it might be a bit useless without a world object to work with in the event. Added.

[cosmicdan]

Hrrrrr..... added one more event that's fired a bit later, allows filtering on CreatureType. Last commit, I promise!

[cosmicdan]

Oh, I completely forgot - you wanted this to be optional and disabled by default. I'll work on that.

I also wanted to add something else, also off by default obviously. This...
entity.getEntityData().setBoolean("JAS_SPAWNED", true);
...to every entity that JAS spawns. This is also for Inter-Mod Communicaton, so other mods can check if a particular entity was spawned into the world via JAS instead of some other method (like spawner machines). In our use case, we have a "score" related to mob kills to accrue only when naturally-spawned mobs are killed to prevent players farming that "score" through e.g. mob farms.

I'll put all of this in a separate "IMC.cfg", with the two options - 1) Fire spawn events and 2) Add entitydata flag - located here, both false.

[cosmicdan]

Ok that's done. Let me know if you want anything changed for the PR.