Dave Matthews surprised fans with a sweet story about his Foreigner fandom during the Rock and Roll Hall of Fame’s plaque dedication ceremony on Friday afternoon in the plaza outside the museum. A number of this year’s inductees – including Peter Frampton, three members of Foreigner (Lou Gramm, Rick Wills and Al Greenwood), Mary J. Blige, Kool & the Gang’s Robert “Kool” Bell and JT Taylor, and Ahmet Ertegun Award recipient Suzanee de Passe – attended the unveiling on a sun-soaked afternoon, in front of several hundred fans who cheered everything from their arrival to their brief comments durin…