In a surprise that stunned the audience of Hollywood’s first big awards-season bash, “A Different Man,” a dark comedy about doppelgängers, deformity and authenticity in acting, won best feature film at the 34th Gotham Awards on Monday night. Much can be unpredictable at the Gotham Awards, which uses small juries of insiders and film industry veterans to pick nominees and winners. “I don’t think I’m not the only person in this room who’s totally stunned,” said Schimberg.