Use failure/success name attribute.

Hi,

when a test fail, I take a screenshot and add some debug info to failure.message:

```
casper.test.on("fail", function (failure) {
    "use strict";
    var capturefile = "reports/casper/" + failure.suite + "." + failure.line + ".png",
        page = "Page: " + casper.getCurrentUrl(),
        screenshot = "Screenshot: " + exports.siteUrl + "/tests/" + capturefile,
        messages = "Console: " + "\n  " + remoteMessages.join("\n  ");
    failure.message = (failure.message? failure.message : failure.standard) + "\n" + [page, screenshot, messages].join("\n");
    casper.capture(capturefile);
});
```

the problem is, the testcase will contain all this debug information.
All I want is have it in the <failure> node.

Thanks.