Chicago built 59 new libraries during the 22-year reign of former Mayor Richard M. Daley. The question now is, what to do with those buildings in a 24/7 digital world where, as Mayor Rahm Emanuel put it, “newspapers are on iPhones and Amazon is your neighborhood bookstore.” Incoming libraries commissioner Brian Bannon says it’s time to “re-envision what libraries look like, both in the physical space as well as in the digital space.”