public static void OnDisconnect(UserContext context)
        {
            Console.WriteLine("Client Disconnected : " + context.ClientAddress);
            var user = OnlineUsers.Keys.Where(o => o.Context.ClientAddress == context.ClientAddress).Single(); // exception here because collection does dot contain the element

            string trash; // Concurrent dictionaries make things weird

            OnlineUsers.TryRemove(user, out trash);

            if (!String.IsNullOrEmpty(user.Name))
            {
                var r = new Response {Type = ResponseType.Disconnect, Data = new {user.Name}};

                Broadcast(JsonConvert.SerializeObject(r));
            }

            BroadcastNameList();
        }