Chicago 10 is a thoroughly entertaining look at the infamous 1969 trial of the group that came to be known as the Chicago 7 — which is to be expected, as its director, Brett Morgen, previously made a similarly inventive and engaging documentary on legendary movie producer Robert Evans, The Kid Stays in the Picture. The two docs couldn’t be about more different subjects, and Morgen wisely ditches the wink-and-a-nod ironies of his previous film…