‘Life Itself’ is a Perfect Biography of Roger Ebert

Oftentimes in documentaries about a celebrity, there’s an interview with a “childhood friend” or some similarly unknown, unverifiable expert on not only the subject’s backstory but also apparently, somehow his or her later years. You can see one of those sorts of talking heads in the new 30 for 30 doc The Price of Gold offering commentary on Tonya Hardi…