Adds more comprehensive bokchoy testing for publishing changes

Now based on bulk-publishing.

@cahrens @andy-armstrong please review.
The other option we have is to use [send_keys](http://selenium-python.readthedocs.org/en/latest/api.html?highlight=send_keys#selenium.webdriver.remote.webelement.WebElement.send_keys) somehow. I will check this test in detail tomorrow.