Stocks turned moderately positive Thursday after showing mixed action. The S&P 500 rose 0.4%, the Dow Jones industrial average added 0.3% and the Nasdaq gained 0.2%. Volume continued to track down from Wednesday's levels across the board. CBS (CBS) rose 3% in heavy turnover, clearing a 36.73 buy point from a cup-with-handle pattern. The media giant has an OK grade of 80 for its IBD Composite Rating, which has a best-possible level of 99. Winnebago