Add Support to define a valid HP range for NPC casting

These will allow us to define a valid HP range (HP of the caster) that
an NPC will cast a spell. For example NPC casting a defensive spell at

zone/perl_npc.cpp

@@ -1993,7 +1993,7 @@ XS(XS_NPC_AddSpellToNPCList)
 		if(THIS == nullptr)
 			Perl_croak(aTHX_ "THIS is nullptr, avoiding crash.");
 
-		THIS->AddSpellToNPCList(priority, spell_id, type, mana_cost, recast_delay, resist_adjust);
+		THIS->AddSpellToNPCList(priority, spell_id, type, mana_cost, recast_delay, resist_adjust, 0, 0);
 	}
 	XSRETURN_EMPTY;
 }