Last May, when ABC announced this season would be Scandal’s last, Shonda Rhimes promises to go “all out” with “white hats on, gladiators running full speed over the cliff.” Here’s how it went. SPOILERS: Final episode, fittingly called Over the Cliff, starts with special prosecutor Lonnie Mencken wanting to make sure if he Olivia Pope the Senate hearing she seeks as part of her image rehab, POTUS Mellie Grant will make gun control a priority. Lonnie previously had agreed…