private void buttonAdd_Click(object sender, EventArgs e)
        {
            int nSel = listBoxBroker.SelectedIndex;

            if (nSel >= 0)
            {
                BrokerItem bi = provider.Brokers[nSel];
                foreach (ServerItem si in bi.Server)
                {
                    provider.Server.Add(si);
                }
                provider.SettingsChanged();
            }
        }
        public void LoadBrokers()
        {
            brokersList.Clear();

            try
            {
                var brokers = from c in XElement.Load(brokersFile).Elements("Broker")
                              select c;

                foreach (var broker in brokers)
                {
                    BrokerItem bi = new BrokerItem()
                    {
                        Label = broker.Attribute("Label").Value
                    };

                    bi.Server = ParseServers(broker.Elements("Server"));

                    brokersList.Add(bi);
                }
            }
            catch (Exception)
            {
            }
        }