Dr. James J. O’Connell, known as “Dr. Jim” to the numberless homeless population he has served over the past 30 years. He is a graduate of Harvard Medical School and currently an assistant professor of medicine there.  Serving Boston’s homeless was not a career path Dr. Jim might normally have chosen upon completion of his residency at MGH.  But once introduced to the work and the people, initially at the Pine Street Inn, he was captivated by the possibilities.  The…