NEW YORK — Nets general manager Sean Marks addressed the media on Tuesday for the first time since Jacque Vaughn was relieved of his coaching duties. A 50-point loss to the Boston Celtics ahead of the All-Star break proved to be the final act of Vaughn’s eight-year tenure with the organization. Marks looks back fondly on Vaughn’s time with the franchise and appreciated the partnership, but the team is obviously far from where it should be at this point in the season, sitting at 21-33 with 28 games left. Marks had to communicate to the players and fans that the on-court product was not living u…