BUGFIX Ensure XML is well formed when rebuilding the XML response. XML i...

...s badly formed when user uses special chars like & or > in the card holder name field. Typical error: "[Warning] simplexml_load_string() [function.simplexml-load-string]: Entity: line 1: parser error : xmlParseEntityRef: no name" when the response is parsed afterwards

A similar PR has been lodged to https://github.com/frankmullenger/silverstripe-payment-paymentexpress/pull/6 for the splitted module