If a movie could ever be credited with capturing and expanding an entire movement, 1977’s “Saturday Night Fever” would be it. In his breakout role, John Travolta starred as Tony Manero, a Brooklynite stuck in a dead-end job and headed for a dead-end life, until he partners with Karen Lynn Gorney and her polyester dresses to hit  the dance floor.  Though best remembered for the Bee Gees’ musical contributions, including the title track and “Staying Alive,” it also included such disco evergreens as the Trammps [CQ] “Disco Inferno.” “SNF” brought disco to the mainstream and spawned an entire three-piece, white-suited lifestyle, for better or worse.