AddNullCouponTest
waitForElementPresent link=Shopping Test Page
clickAtAndWait link=Shopping Test Page
clickAtAndWait link=Coupons
clickAtAndWait //input[@value='Add Coupon']
clickAtAndWait //input[@value='Save']
assertTextPresent You have entered invalid data. Please try again.
assertTextPresent Please enter a valid code.
clickAtAndWait link=Return to Full Page