MINEOLA, N.Y. (AP) -- Like many commuters, Ron Marino is incredulous about revelations that nearly every employee who asked for disability benefits after retiring from the nation's largest commuter railroad was granted them. But Marino isn't the only one who is venting these days about the Long Island Rail Road. Four separate investigations are under way after it was reported last month that more than 90 percent of Long Island Rail Road employees were granted disability payments by an obscure federal board, allowing them to collect huge payments every year. The New York Post has dubbed this the ''Gravy Train...