Disco itself is synonymous with Donna Summer’s ebullient and endlessly groovable smash “Bad Girls.” But Summer’s album of the same name, released in 1979, is replete with myriad gems that didn’t receive quite as many ecstatic spins on the dancefloors of the era, from the new wave stomp of “Sunset People” to “On My Honor,” a slow-jam to sway to as the late night seeps into the early morning.