code: private String printStackTrace(Object[] stackTrace) {
          StringBuilder output = new StringBuilder();
          for (Object line : stackTrace) {
              output.append(line);
              output.append(newline);
          }
          return output.toString();
      }
docs: Given a stack trace, turn it into a HTML formatted string - to improve its display
  
  @param stackTrace - stack trace to convert to string
  @return String with stack trace formatted with HTML line breaks