Allow for ignore/target filters to support mobtypes/mythicmobtypes

Summary

Currently, you can filter things like players, hostile, animals etc in the ignore/target filters for targeters, but it would be great if you could specify a specific mythicmob type to filter.

Usage

Instead of using a condition to filter a specific mob type, you could do the following:

skill{s=ASkill} @ThreatTable{r=5;target=MyOtherMob}

Which would allow you to specifically target a mob within a ThreatTable for example.

Value

The benefit of this is that you can have more precise control over what to target before a skill is even run. Additionally, allows you to reduce the number of conditions necessary to check mobs and would also help to prevent issues where there could potentially be a NullPointerException for targeting multiple entities (such as when using variables).

Priority

3 - Butts (Nellabel told me to do it).

I feel this would be a great overall addition for more refined control of what mobs should be targeted, therefore should be a higher priority.

Implementation

# This allows you to specifically target a type of MythicMob inside of a 
# ThreatTable without affecting *all* ThreatTable targets.
skill{s=ASkill} @ThreatTable{r=5;target=MyOtherMob}

# This would allow you to target all entities in the world except 
# MyOtherMob (useful if you have a mob that you want to be ignored for a global effect).
skill{s=ASkill} @LivingInWorld{ignore=MyOtherMob}

# This would allow you to run a skill on all children except MyOtherMob 
# (very useful if you have multiple types of children mobs).
skill{s=ASkill} @Children{ignore=MyOtherMob}