Once again the hunt is on for a group of subway riders who rescued a fellow straphanger who fell onto the tracks. Alexa Conto, a 20-year-old fashion student, tells the Daily News that she believes she fainted while waiting for the D train at Brooklyn’s 71st Street station on Tuesday morning. Several people jumped onto the tracks to save her, and the MTA operator spotted them and stopped the train just in time. New Yorkers can be pretty decent, when we aren’t beating each other with crutches.