ARLINGTON – Jimmy Johnson just capped a football life – featuring two Super Bowls titles, membership of the Pro Football Hall of Fame and now an induction into the Dallas Cowboys’ Ring of Honor with a halftime speech for the ages here at AT&T Stadium … all the while surrounded by some of his greatest players – Ring of Honor members themselves. And how did he quite naturally punctuate that speech? “How ‘bout them Cowboys!” Jimmy barked, at which point he was mobbed by the likes of Michael Irvin, Emmitt Smith and Charles Haley. “At times,” Jimmy said to his…