migrate to "export default"

also, set no-use-before-define in linter

src/community.js

@@ -8,12 +8,6 @@ import superagent from '@cloudron/superagent';
 
 const debug = debugModule('box:community');
 
-export {
-    getAppVersion,
-    downloadManifest,
-    getAppUpdate,
-    downloadIcon
-};
 
 async function getAppVersion(url, version) {
     assert.strictEqual(typeof url, 'string');
@@ -120,3 +114,10 @@ async function downloadIcon(manifest) {
         return response.body;
     });
 }
+
+export default {
+    getAppVersion,
+    downloadManifest,
+    getAppUpdate,
+    downloadIcon
+};