In 1999, a series premiered on HBO that would change television: “The Sopranos,” the saga of a New Jersey crime family headed by Tony Soprano, an anti-hero who enters therapy to question a lifetime of violence and corruption. Correspondent Anthony Mason talks with series creator David Chase, and the show’s stars Edie Falco, Steven Van Zandt, Michael Imperioli and Steve Schirripa, about the personal and cultural impact of “The Sopranos”; about the late James Gandolfini, whose performance as Tony Soprano Chase calls “otherworldly”; and about the series’ controversial finale.