Improve flattening of results from pushAdapter

spec/PushController.spec.js

@@ -1,6 +1,6 @@
 "use strict";
 var PushController = require('../src/Controllers/PushController').PushController;
-
+var pushStatusHandler = require('../src/pushStatusHandler');
 var Config = require('../src/Config');
 
 const successfulTransmissions = function(body, installations) {
@@ -357,4 +357,8 @@ describe('PushController', () => {
     });
   });
 
+  it('should flatten', () => {
+    var res = pushStatusHandler.flatten([1, [2], [[3, 4], 5], [[[6]]]])
+    expect(res).toEqual([1,2,3,4,5,6]);
+  })
 });