Minor issue in Open API 2.0 WInForms Sample

Dear all,

in the current version "Get Transactions" returns an error as the time range exceeds the maximum of 1 week.

To fix it the following change needs to be done in Main.cs (from):

private void btnGetTransactions_Click(object sender, EventArgs e)
        {
            var msgFactory = new OpenApiMessagesFactory();
            var msg = msgFactory.CreateCashflowHistoryRequest(_accountID, ((DateTimeOffset)DateTime.Now.AddDays(-5)).ToUnixTimeMilliseconds(), ((DateTimeOffset)DateTime.Now).ToUnixTimeMilliseconds());
            Transmit(msg);
        }

Hope this helps.

Regards,
Christian