As rescuers pick through the rubble of buildings crushed and damaged by a crane collapse in midtown Manhattan yesterday, real estate developer James Kennelly was familiar with the scene because he served 13 years with the FDNY, where he had been assigned to Ladder 16 in Manhattan on East 67th St. The developer of 303 East 51st St., a planned 40+ floor skyscraper where the crane was situated, Kennelly earned a bachelor and law degree......