Using xalan::ProblemListenerBase formatting functionality in ErrorCapacitor
* xalan::ProblemListenerBase provides a static member method called "defaultFormat"
** this method provides formatting of problem messages into xalan::XalanDOMString instances when combined with xalan::DOMStringPrintWriter
* there is no need for implementing custom message formatting
** the only reason why ErrorCapacitor exists is so we are able to capture and print messages at our own volition