AM - Mobs leveling system

[NEW] Only specific mods can be leaders now (you can change this in the new settings only_leaders list)

[NEW] Killing leader gives extra XP configurable in the main config leader_extra_xp

[NEW] Leaders now have a special name and bar color

[NEW] When You hit the leaders now at 25% HP of its max health Random Events can happen

(Spawn Backup skeletons - explode in a power of 4 - Spawn a falling anvil on top of you - set you on fire for 15 secs)