By Don Heckman Los Angeles – Mar. 1. (Tues.)  Alan Bergman.  It’s always fun to hear a songwriter perform his own songs.  But it’s even better when the songwriter is also a singer with a richly nuanced interpretative style.  In Bergman, you get all that and more.  Vibrato Grill Jazz…etc.   (310) 474-9400.  http://www.vibratogrilljazz.com – Mar.… Read More Picks of the Week: Mar. 1 – 6