By Alicia Powell NEW YORK (Reuters) – An unlikely art heist by a compassionate cab driver over 60 years ago is now a fun dramedy starring British actors Dame Helen Mirren and Jim Broadbent. “The Duke,” out in New York and Los Angeles theaters on Friday, follows 60-year-old Kempton Bunton as he steals Spanish master Francisco de Goya’s portrait of the Duke of Wellington from the National Gallery in London in 1961. The thief sends ransom notes saying he will return the painting on condition that the British government invests more for elderly care. “I didn’t know anything about this story. I was…