The gentrifying core of Bushwick occupies only a few blocks, and for Rabbi Menachem Heller, 29, herein lies the problem. As an emissary of the Chabad-Lubavitch movement, a branch of Hasidic Judaism that emphasizes outreach to less observant Jews, Rabbi Heller wants good access to the hipster arrivistes. Unfortunately, his current spot is too far away from the few hangouts ...