When Mickey Gitzin arrived in New York last month with two young daughters and a few winter coats hastily packed in Israel, he was stepping into a role that once would have seemed improbable for the organization he now leads.Gitzin, 44, was named interim president and CEO of the New Israel Fund in December, as its longtime CEO, Daniel Sokatch, begins a year-long sabbatical. Gitzin takes over at an organization that funds progressive Jewish and Arab organizations in Israel that are often at odds