Improve eslint rules (#3147)

* Add semi to ESLint rules

* Add padded-blocks to ESLint rules

* Add comma-dangle to ESLint rules

* add config/webpack and storyboard

* add streaming/

* yarn test:lint -- --fix

app/javascript/mastodon/features/status/components/detailed_status.js

@@ -15,7 +15,7 @@ import ImmutablePureComponent from 'react-immutable-pure-component';
 class DetailedStatus extends ImmutablePureComponent {
 
   static contextTypes = {
-    router: PropTypes.object
+    router: PropTypes.object,
   };
 
   static propTypes = {