Adding casper test reporting for pass, fail, and timeout events

I'd suggest replacing the console output for test fails and timeouts with the Casper test reporting methods: pass, fail, and info.

These methods also provide console output, but allow PhantomCSS passes and fails to be reported alongside other Casper tests.

In addition, you can get the results from PhantomCSS tests in jUnit XML, which can be processed by build systems. For example, by using renderResults:

```
casper.
  then(function now_check_the_screenshots() {
	phantomcss.compareAll();
  }).
  run(function end_it() {
	console.log('\nTEST COMPLETE.');
	casper.test.renderResults(false, 0, 'test-results.xml');
	phantom.exit(phantomcss.getExitStatus());
  });
```