remove sauce option for selenium version. replace 'iehta' with 'internet...

... explorer'

in reference to issue experienced with grunt-saucelabs https://github.com/axemclion/grunt-saucelabs/issues/154

The browser 'iehta' is used only for Selenium RC. Selenium webdriver uses 'internet explorer'. Switching the browser name causes Sauce Labs to use Selenium Webdriver, and tests pass/fail respectively.