New Perl/Lua buff functionality.

- Mob::FindBuffBySlot(slot)
	This allows you to find buffs by a specific slot.
	Example: https://i.imgur.com/VG68cxs.png
	Perl Example: https://pastebin.com/8HvMAC4h

- Mob::BuffCount()
	This will find the active number of buffs an NPC/client has.
	Example: https://i.imgur.com/jrLRBwV.png
	Perl Example: https://pastebin.com/Wmg16wwp

zone/mob.h

@@ -385,6 +385,8 @@ public:
 	void DamageShield(Mob* other, bool spell_ds = false);
 	int32 RuneAbsorb(int32 damage, uint16 type);
 	bool FindBuff(uint16 spellid);
+	uint16 FindBuffBySlot(int slot);
+	uint32 BuffCount();
 	bool FindType(uint16 type, bool bOffensive = false, uint16 threshold = 100);
 	int16 GetBuffSlotFromType(uint16 type);
 	uint16 GetSpellIDFromSlot(uint8 slot);