Positive earnings reports and sunny economic news bolstered stocks Wednesday.   The jobless claims report pleasantly surprised investors plunging to 335 000 well below expectations of 368 000 claims. The PMI Manufacturing Index Flash also provided positive news for business growth. The reading for December was 54.0 up 1.2 points from November's reading and the highest since May of last year.   The Dow (INDEXDJX:.DJI) moved up 54 points to 13766.59.  The S&P 500 (INDEXSP:.INX) declined 0.04% to 1491.84 and the Nasdaq (INDEXNASDAQ:.IXIC) rose to 3154.91 up 0.37%.   International Business Machines' (NYSE:IBM) earnings per share rose to $14.37 ...