Jerry Holt is the author of "Rickey," a play based on the life of baseball guru Branch Rickey, the man who changed civil rights history when he brought Jackie Robinson into the Major Leagues in 1947.   "Rickey" has been performed across the US, most memorably in Brooklyn at LIU and in Cooperstown at the Baseball Hall of Fame.  Holt's novel "The Killing of Strangers," a thriller based on the shooting at Kent State University in 1970, was chosen last November as a finalist in the St. Martin's First Mystery Competition.  By day, Holt is Dean of Arts and Sciences at Shawnee State University in Portsmouth, Ohio.