NEW YORK (Reuters) - Rapper Jay-Z and Justin Timberlake are teaming up for a 12-city summer stadium tour that will include concerts in New York, Los Angeles, San Francisco and Chicago, music promoter Live Nation said on Friday. The "Legends of the Summer" tour will kick off at the Roger's Center in Toronto on July 17, and finish on August 16 at the Sun Life Stadium in Miami. Venues in Boston, Detroit and Baltimore will also be included in the tour. ...