Anew and fiery Byron W. Brown sought to revive his failed mayoral campaign Monday with a whole new persona. Gone was the aloof incumbent seemingly self-assured of an unprecedented fifth term leading Buffalo. Instead, Brown launched a "do over" candidacy, passionately announcing in the Statler Terrace Room a write-in campaign for the Nov. 2 general election to reclaim the office he preliminarily lost to newcomer India B. Walton on June 22. "I say not yet," he said with about two dozen cheering su