It looks as though Justin Bieber has got a long career ahead of him as his mentor Usher has revealed that the 16-year-old has "so much in store for the future."Usher revealed MTV News: "As far as music and entertainment, that's the begining."There's so much more in store for the future, or at least there's a ton of things we can do and will, and with the support of his fans who will continue to