[Performance] Client / NPC Position Update Optimizations (#4602)

* Zone optimizations

* More changes

* More

* Update entity.cpp

* Beautiful

* Amazing

* Feature flag all logic

* Broadcast to group

* Update mob.cpp

* Updates

* Update client.cpp

* Update client.cpp

* Add rule Zone:EnableEntityClipping

* Little bit of cleanup

* Don't send update to self while in group

* Remove visibility work and feature flags

* Cleanup

* Logging

* Improve CheckSendBulkNpcPositions

* No need to cast

* Field cleanup

* Build initial list on zone-in

common/eqemu_logsys.h

@@ -143,6 +143,7 @@ namespace Logs {
 		Corpses,
 		XTargets,
 		EvolveItem,
+		PositionUpdate,
 		MaxCategoryID /* Don't Remove this */
 	};
 
@@ -244,7 +245,8 @@ namespace Logs {
 		"EqTime",
 		"Corpses",
 		"XTargets",
-		"EvolveItem"
+		"EvolveItem",
+		"PositionUpdate"
 	};
 }