Upgrade to Selenium 2.8.0

v2.8.0
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WebDriver
  * FIXED: 1967,1934: Temporary directories no longer fill up disk.
  * FIXED: 2295,1899: Better handling of select/option tags in HtmlUnit
  * Disabled elements won't be cleared any more
  * FIXED: 2531: Allow setting frozen firefox profile preferences to their frozen values.
  * FIXED: 2509: Fixing error=24 too many open files bug
  * Added setFileLocator to RemoteWebDriver to allow files to be uploaded to the remote server
  * Faster error reporting if chromedriver isn't executable
  * FIXED: Occasional ClassCastExceptions
  * FIXED: Proxy configuration NullPointerException problem
  * FIXED: 1326: Allow parallel execution of FirefoxDriver on Linux with native events
  * FIXED: 384: Fixed native FirefoxDriver crash on some 64-bit linux systems
  * FIXED: 417: Allow @FindBy annotations to be put on List<WebElement> as well as just WebElement fields
  * Added native event support for Firefox 7
  * Added constructor to ChromeDriver that lets you specify the ChromeDriverService as well as the DesiredCapabilities
  * FIXED: By.linkText now always trims leading and trailing whitespace
  * FIXED: Issues with doubleClick in Firefox

RC
  * FIXED: 1934: -singleWindow works for *iexplore
  * Selenium Server params work with RC Grid configuration
  * Adding support for Firefox 8