By Julian Linden AUGUSTA, Georgia, April 12 (Reuters) - China's teenage golf sensation Guan Tianling was penalised for slow play at the Masters on Friday, jeopardising his chances of becoming the youngest player ever to make the cut at a major championship. Officials imposed a rare one-stroke penalty on the 14-year-old after he was warned for taking too much time during his second round at Augusta National. With the addition of the penalty, Guan completed a second round of three-over-par 75 for a 36-hole total of four-over, leaving him right on the cusp of the projected cut. ... More...