“Dance of Death’’ isn’t the most cheerful-sounding title, especially for the story of a marriage. But Sunday evening’s reading at the Paramount Center of August Strindberg’s 1900 drama is the kickoff to Boston events that are part of the international Strindberg 2012 Festival. The celebration, which continues here in March, is an effort by Strindberg scholars to lift the famously gloomy Swedish playwright’s profile on the 100th anniversary of his death.