Not so long ago, Moran’s eclectic, adventurous approach to jazz would have placed him well outside the aesthetic boundaries of Washington’s John F. Kennedy Center for the Performing Arts . But in the past few years, the big white box on the Potomac has opened its venues to jazz in tandem with skateboarders, stand-up comics, dancers, painters and rappers. This redefining of what it means to be the “national cultural center” is, to a large extent, the doing of Jason Moran.