Add some linting rules for the CI (#587)

* enable one-var rule

* enable indent rule

* enable no-multiple-empty-lines rule

* enable no-empty rule

* enable no-trailing-spaces rule

* enable no-extra-semi rule

* add eslint rules to fix block spacing

* enable max-statements-per-line rule

* enable brace-style rule

* fix some spacing issues and add future rules

* add code suggestions

src/components/emby-tabs/emby-tabs.js

@@ -142,7 +142,7 @@ define(['dom', 'scroller', 'browser', 'layoutManager', 'focusManager', 'register
             tabs.classList.add('scrollX');
             tabs.classList.add('hiddenScrollX');
             tabs.classList.add('smoothScrollX');
-       }
+        }
     }
 
     EmbyTabs.createdCallback = function () {