MIAMI — The Florida Panthers have plundered the Buffalo Sabres for key contributors to help build a Stanley Cup contender in the last year and made their return to Western New York on Monday, for the most part, a good one. Brandon Montour, who played parts of three seasons for the Sabres before the Panthers dealt for him ahead of the trade deadline last year, scored the opening goal on Florida’s first shot in the first period. Sam Reinhart, whom Buffalo took second overall in the 2014 NHL Entry Draft and traded to the Panthers in the offseason, had a second-period assist while Florida pulled a…