FEATURE: New 'Reviewable' model to make reviewable items generic

Includes support for flags, reviewable users and queued posts, with REST API
backwards compatibility.

Co-Authored-By: romanrizzi <romanalejandro@gmail.com>
Co-Authored-By: jjaffeux <j.jaffeux@gmail.com>

app/assets/javascripts/polyfills.js

@@ -178,4 +178,5 @@ if (!Array.prototype.find) {
     writable: true
   });
 }
+
 /* eslint-enable */