Fix semicolons and throw error in ESLint if missing

src/scripts/dfnshelper.js

@@ -101,4 +101,4 @@ export const localeWithSuffix = { addSuffix: true, locale: getLocale() };
 export default {
     getLocale: getLocale,
     localeWithSuffix: localeWithSuffix
-}
+};

src/scripts/site.js

@@ -323,11 +323,11 @@ var AppInfo = {};
     }
 
     function getElementsPath() {
-        return "elements"
+        return "elements";
     }
 
     function getScriptsPath() {
-        return "scripts"
+        return "scripts";
     }
 
     function getPlaybackManager(playbackManager) {