OXFORD, Md. — Long before there was a “Black Lives Matter” movement, there was Ruth Starr Rose, an activist artist whose paintings nearly a century ago captured the dignity and spirit of America’s black families at a time when stereotype and caricature prevailed. It is fitting that an exhibition of her early 20th century work should find its way this week to Baltimore and the Reginald F. Lewis Museum as the city continues to recover from the tragic death of Freddie Gray. Rose, who died in 1965, would have recognized the Gray incident and ensuing riots as all too familiar.