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/Misc/Profile.cs

@@ -64,7 +64,7 @@ namespace Server.Misc
 			if ( a == null )
 				return "";
 
-			TimeSpan ts = DateTime.Now - a.Created;
+			TimeSpan ts = DateTime.UtcNow - a.Created;
 
 			string v;