easier to do that in the nontwitter age. enough of the real news, let s gather around the water cooler to talk about a once in a lifetime moment in rock and roll history. sir paul mccartney joined the boss, bruce springsteen on stage sunday night in london s hyde park. the only problem, their mikes were cut out by concert organizers before they were done. are you kidding me? nbc s duncan golasani has the full report pulitzer journalism right here. two, three, four reporter: two music legends, one one incredible finale. until that is, someone cut the microphones. springsteen s good-bye silent to the crowd. and just left the sound of booing. among the 65,000 fans, was nbc s kier simmons. they didn t seem to know what was going on, you ve got