modal and layout

android/app/src/main/java/com/reactnativenavigation/controllers/Modal.java

+package com.reactnativenavigation.controllers;
+
+public class Modal {
+}

android/app/src/main/java/com/reactnativenavigation/controllers/ModalController.java

 
 public class ModalController {
 
-    private final Stack<RnnModal> modals;
+    private final Stack<RnnModal> modals = new Stack<>();
 
     public ModalController() {
-        modals = new Stack<>();
     }
 
     public void add(RnnModal modal) {

android/app/src/main/java/com/reactnativenavigation/layouts/Layout.java

+package com.reactnativenavigation.layouts;
+
+public interface Layout {
+}

android/app/src/main/java/com/reactnativenavigation/modal/RnnModal.java

 import com.reactnativenavigation.views.RnnToolBar;
 import com.reactnativenavigation.views.ScreenStack;
 
-/**
- * Created by guyc on 02/05/16.
- */
 public class RnnModal extends Dialog implements DialogInterface.OnDismissListener {
 
     private ScreenStack mScreenStack;