SHE DIDN’T JUST SING JAZZ — SHE STRETCHED ITS BOUNDARIES. Cassandra Wilson, the Grammy-winning singer, songwriter and producer whose deep, smoky contralto became one of the most distinctive voices in contemporary jazz, has died at 70. Wilson died September 1 at her home in Jackson, Mississippi, surrounded by family, close friends and her manager. Born in Jackson on December 4, 1955, Wilson grew up surrounded by music. Her father was a guitarist, bassist and music teacher with