Implement Core.TickCount

Convert movement, actions (lift/use), combat, and spells to use Core.TickCount and avoid DateTime caveats (performance, system time dependency, etc)
Refactor DateTime.Now to DateTime.UtcNow
Add LOS check for Iron Maiden addon

Scripts/Commands/Docs.cs

@@ -28,11 +28,11 @@ namespace Server.Commands
 			Network.NetState.FlushAll();
 			Network.NetState.Pause();
 
-			DateTime startTime = DateTime.Now;
+			DateTime startTime = DateTime.UtcNow;
 
 			bool generated = Document();
 
-			DateTime endTime = DateTime.Now;
+			DateTime endTime = DateTime.UtcNow;
 
 			Network.NetState.Resume();