Alicia Keys would love to headline Glastonbury one day. The 43-year-old singer recently performed alongside Usher at the Super Bowl in Las Vegas, and Alicia now has her sights set on headlining the world-famous festival in south-west England. Alicia told The Sun newspaper’s Bizarre column: “With the Super Bowl, when you prepare for something like that your heart is racing. “Even though I am not doing a dance, your voice can’t keep up with it because of the adrenaline. “When you’re chilling in your room and then you are out there in front of 80,000 in the stadium it is ridiculous. “It has train…