Moved test evaluation to the page.onLoadFinished callback.

I've moved the test evaluation to the ```page.onLoadFinished``` callback so that we know the page has finished loading before we start tests. 

Also, I found a test that was failing/infinite looping and hanging the test run. I'll get this test fixed and put it back into the list of tests shortly. 

I've commented out this test in the latest release of Quail and made a few more changes so that Success Criteria always finish regardless of if they apply. This should get us to a place where the test evaluations always run and complete in your accessibility monitor.

Run the code in this pull request against Quail version https://github.com/quailjs/quail/tree/2.2.4