(From DCist contributor Kanishka Gangopadhyay) A national star-studded musical tour organized by the online organization Moveon.org will culminate with a massive concert on October 11th in Washington D.C.’s MCI center, the group announced today. Thus far, the artists have been touring the country separately as individual participants in the nationwide Vote For Change Tour. The concert will most likely be the largest concert event to hit D.C. this fall. The concert’s eclectic 13-performer lineup includes…