* CreditCards.cs: Additional tests for fetching cards.

* Gateway.cs: Added exception handling for connection issues (timeouts
  etc). 

* CreditCard.cs: Added method to fetch (find) a card.
Added code to check for null values when parsing a response to prevent
  null ref exceptions.


* Response.cs: Added logging around the parsing to help make debugging
  issues for developers easier. Writes response to Debugger window.

* AssemblyInfo.cs: Version update.