Christopher Vourlias Colombia’s Germán Arango and Ana María Muñoz, the director-producer duo behind Hot Docs International Spectrum competition title “Songs That Flood the River,” are prepping a host of new documentary and fiction features focused on race, gender, violence and resistance in the South American nation, Variety has learned.Arango is developing “MC Silencio,” a Medellín-set musical drama in which the young resist and fight paramilitary aggression through hip-hop, and “The Man With