“Line-e Ashen” is NOT an announcement you hear at the station or airport, asking people to form a queue. It's a Bangla, cooler/hipper alternative to the English “straighten up”.
The bottom line is simple, a direct call for all the numpties out there to get their acts straight and start behaving like responsible citizens with some functioning brain cells for once. Every day we encounter many situations that require the usage of “line-e ashen/asho” but most of time, we can't. At least once a day you wish you could say to some politician, “Bhai, line-e ashen”.