[youtube https://www.youtube.com/watch?v=rLv0NH-lJUc?enablejsapi=1&] Anyone who purchases a copy of Mario Kart 8 up to two months after its May 30 release will be able to download one of four Wii U games for free, Nintendo announced Wednesday. Players can choose from Pikmin 3, New Super Mario Bros. U, The Legend of Zelda: The Wind Waker HD…