Wilco frontman Jeff Tweedy has announced a two month-long national tour in support of an upcoming solo album. The shows, which will be “loosely staged in two parts” of old songs and unreleased ones, will also feature an new back-up band that includes his 18-year-old son Spencer on drums. The tour kicks-off on June 5 in Detroit and includes a few Canadian dates before wrapping at Newport, Rhode Island’s Folk Festival on July 27 …