Make app auto install as part of async flow

It was called in nextTick() and was done async but had no chance to
run because the platform.initialize() which is sync was blocking it

src/cloudron.js

@@ -121,13 +121,10 @@ CloudronError.SELF_UPGRADE_NOT_SUPPORTED = 'Self upgrade not supported';
 function initialize(callback) {
     assert.strictEqual(typeof callback, 'function');
 
-    if (!fs.existsSync(paths.FIRST_RUN_FILE)) {
-        debug('initialize: installing app bundle on first run');
-        process.nextTick(installAppBundle);
-        fs.writeFileSync(paths.FIRST_RUN_FILE, 'been there, done that', 'utf8');
-    }
-
-    syncConfigState(callback);
+    async.series([
+        syncConfigState,
+        installAppBundle
+    ], callback);
 }
 
 function uninitialize(callback) {
@@ -754,14 +751,14 @@ function doUpdate(boxUpdateInfo, callback) {
 }
 
 function installAppBundle(callback) {
-    callback = callback || NOOP_CALLBACK;
+    assert.strictEqual(typeof callback, 'function');
+
+    if (fs.existsSync(paths.FIRST_RUN_FILE)) return callback();
 
     var bundle = config.get('appBundle');
+    debug('initialize: installing app bundle on first run: %j', bundle);
 
-    if (!bundle || bundle.length === 0) {
-        debug('installAppBundle: no bundle set');
-        return callback();
-    }
+    if (!bundle || bundle.length === 0) return callback();
 
     async.eachSeries(bundle, function (appInfo, iteratorCallback) {
         debug('autoInstall: installing %s at %s', appInfo.appstoreId, appInfo.location);
@@ -777,6 +774,8 @@ function installAppBundle(callback) {
     }, function (error) {
         if (error) debug('autoInstallApps: ', error);
 
+        fs.writeFileSync(paths.FIRST_RUN_FILE, 'been there, done that', 'utf8');
+
         callback();
     });
 }