On behalf of  shijunjuan: Handling possible IllegalStateException while cleaning orphaned and timed out sessions. Fixes issue 6771
Adding a new selenium server option -logLongForm to log more details to the console. Fixes issue 6645
Propagate webdriver_firefox_port preference to FirefoxDriver, was being ignored. Fixes issue 5172

Signed-off-by: Alexei Barantsev <barancev@gmail.com>