Gulp task to run protractor tests

Gulp task to start `protractor` tests. Before running tests it ensures webdriver is installed (`ensure_webdriver_standalone`) and starts it (`webdriver_standalone`).

Usage:
```
gulp test
```
To be clear, I'm fine going with route.  I don't want to block anything over this.

However, I would also like to say that in my experience, niggling "bugs" or behaviors in a testing system, for example intermittent failures in tests, breeds a culture of ignoring the test results.  I don't want that for us.