Cleanup & Fixes for .NET 5 (#309)

- [X] Fixes several bugs
- [X] Updates more ordinal issues
- [X] Cleans up the code a bit
- [X] Turns classes static that should have been
- [X] Changes TcpServer.Instances to a HashSet

Bumps release version

Projects/UOContent/Commands/Generic/Implementors/IPAddressCommandImplementor.cs

@@ -38,11 +38,8 @@ namespace Server.Commands.Generic
                 var list = new List<object>();
                 var addresses = new List<IPAddress>();
 
-                var states = TcpServer.Instances;
-
-                for (var i = 0; i < states.Count; ++i)
+                foreach (var ns in TcpServer.Instances)
                 {
-                    var ns = states[i];
                     var mob = ns.Mobile;
 
                     if (mob != null && !addresses.Contains(ns.Address) && ext.IsValid(mob))