Invisible/Hide mechanics when cast on

Updated mechanics to be consistent with live regarding how invisible breaks when the client is the target of a spell.
Invisible will drop whenever a client is hit with a detrimental spell, regardless of if resisted, if it does damage or AOE.
Hide skill now also follows the same rules as above.
Implemented support for Rogue AA - Nerves of Steel which gives a chance for hide NOT to break
when client is hit with an AOE spell.

zone/client.h

@@ -878,6 +878,7 @@ public:
 	void SetFilter(eqFilterType filter_id, eqFilterMode value) { ClientFilters[filter_id]=value; }
 
 	void BreakInvis();
+	void BreakSneakWhenCastOn(Mob* caster, bool IsResisted);
 	void LeaveGroup();
 
 	bool Hungry() const {if (GetGM()) return false; return m_pp.hunger_level <= 3000;}