Add hot_zone filtering for global loot

We do this in GlobalLootEntry::PassesRules since we want to check if the
hot zone status changes during run time

Value can be null, if null it's not checked. If the value is 0 the zone
must not be a hot zone (I guess one might want that) and if it's not 0,
the zone must be a hot zone

zone/global_loot_manager.h

@@ -17,6 +17,7 @@ enum class RuleTypes {
 	BodyType = 4,
 	Rare = 5,
 	Raid = 6,
+	HotZone = 7,
 	Max
 };