When it comes to the arts and San Francisco,  one name comes up often – Ruth Asawa.  Her footprint can be felt across the city … from sculptures to landscape designs to fountains. She was so prolific … that her works are now taking up a dozen galleries at the San Francisco Museum of Modern Art.  A new retrospective just opened this week - and here to tell us more is Sarah Hotchkiss, senior associate editor for KQED Arts.