Paul McCartney is giving thumbs up to Tenacious D's cover of an Abbey Road classic. JB & KG have been performing their version since they started playing live shows back in the '90s. They just recorded an official version of the Beatles medley "You Never Give Me Your Money" and "The End." The Greatest Band on Earth also shot an official video with the song. Black says in his post that the new track is a fundraiser for the nonprofit organization Doctors Without Borders. Paul McCartney actually shared the video on his Facebook page....