support multiple modals shows

ios/RNNBridgeModule.m

 	RNNControllerFactory *factory = [[RNNControllerFactory alloc] initWithRootViewCreator:[RNNReactRootViewCreator new] store:[RNN instance].store];
 	UIViewController *newVc = [factory createLayoutAndSaveToStore:layout];
 	
-	[UIApplication.sharedApplication.delegate.window.rootViewController presentViewController:newVc animated:YES completion:^{
+	UIViewController *root = UIApplication.sharedApplication.delegate.window.rootViewController;
+	while(root.presentedViewController) {
+		root = root.presentedViewController;
+	}
+	
+	[root presentViewController:newVc animated:YES completion:^{
 		
 	}];
 }
 
 RCT_EXPORT_METHOD(dismissModal:(NSString*)containerId)
 {
-	[UIApplication.sharedApplication.delegate.window.rootViewController dismissViewControllerAnimated:YES completion:^{
+	UIViewController *root = UIApplication.sharedApplication.delegate.window.rootViewController;
+	while(root.presentedViewController) {
+		root = root.presentedViewController;
+	}
+
+	
+	[root dismissViewControllerAnimated:YES completion:^{
 		
 	}];
 }

playground/e2e/app.test.js

     expect(elementByLabel('React Native Navigation!')).toBeVisible();
   });
 
-  xit('show multiple modals', () => {
+  it('show multiple modals', () => {
     elementByLabel('Show Modal').tap();
     expect(elementByLabel('Modal Stack Position: 1')).toBeVisible();
     elementByLabel('Show Modal').tap();