By DCist Contributor Steve Kiviat The Smithsonian Folklife Festival has a somewhat well-deserved reputation as a highly educational place to dump visiting relatives, but tourists and discerning locals alike can also have some fun at the event’s daytime performances and evening concerts and dance parties (not to mention chowing down on grub that’s better than street-corner hotdogs). This year’s 41st annual version features three themes: “Mekong River: Connecting Cultures,” “Northern Ireland at the Smithsonian,” and…