CHILMARK, Mass. – President Barack Obama played tennis with his wife and golf with his buddies Monday, starting his first vacation in office on Martha's Vineyard, a picturesque island known as a refuge for the wealthy and privileged. Obama began the day with a workout at his rented retreat, then tennis with Michelle Obama, White House spokesman Bill Burton told reporters traveling with the president. Obama later played golf with UBS Investment Bank President Robert Wolf and Chicago physician Eric Whitaker, both friends. White House aide Marvin Nicholson was also in the foursome. White House officials have stressed that the...