The Pay Now button on CreditCardPayment.html can be clicked multiple times
The button should disable itself when clicked until we've received a response from the Aeon server or otherwise timed out.
If the billing amount is 0, it is not halting the process. You can't click a button until there is a value for the transaction number or the billing amount.
Released in Aeon v5.1 and v5.0.73 default web pages