Mindy Glickman and Jon Nissenblatt learned a lot from their father, acquiring expertise and skill that requires them to exercise "crowd control" when prom season arrives. The brother and sister duo run Marty's Formal Wear, Inc. in Cortlandt Manor. Handfuls of young men gathered outside the Main Street shop Wednesday, waiting for their turn to try on the tuxedo they'll wear to prom. On days like that, when teens from as many as five high schools across the area show up fo