title: Bootstrap method returned null - Android crash immediately on launch
body: <p>Newbie to React Native and react-native-navigation.  App works correctly on iOS but throws the exception below very quickly on launch:</p>
  
  <pre><code>E/AndroidRuntime: FATAL EXCEPTION: main
      Process: com.engagereact, PID: 8105
      java.lang.BootstrapMethodError: Exception from call site #3 bootstrap method
          at com.reactnativenavigation.react.JsDevReloadHandler.&lt;init&gt;(JsDevReloadHandler.java:29)
          at com.reactnativenavigation.react.ReactGateway.&lt;init&gt;(ReactGateway.java:29)
          at com.engagereact.MainApplication.createReactGateway(MainApplication.java:29)
          at com.reactnativenavigation.NavigationApplication.onCreate(NavigationApplication.java:28)
          at android.app.Instrumentation.callApplicationOnCreate(Instrumentation.java:1154)
          at android.app.ActivityThread.handleBindApplication(ActivityThread.java:5871)
          at android.app.ActivityThread.access$1100(ActivityThread.java:199)
          at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1650)
          at android.os.Handler.dispatchMessage(Handler.java:106)
          at android.os.Looper.loop(Looper.java:193)
          at android.app.ActivityThread.main(ActivityThread.java:6669)
          at java.lang.reflect.Method.invoke(Native Method)
          at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
          at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)
       Caused by: java.lang.ClassCastException: Bootstrap method returned null
          at com.reactnativenavigation.react.JsDevReloadHandler.&lt;init&gt;(JsDevReloadHandler.java:29) 
          at com.reactnativenavigation.react.ReactGateway.&lt;init&gt;(ReactGateway.java:29) 
          at com.engagereact.MainApplication.createReactGateway(MainApplication.java:29) 
          at com.reactnativenavigation.NavigationApplication.onCreate(NavigationApplication.java:28) 
          at android.app.Instrumentation.callApplicationOnCreate(Instrumentation.java:1154) 
          at android.app.ActivityThread.handleBindApplication(ActivityThread.java:5871) 
          at android.app.ActivityThread.access$1100(ActivityThread.java:199) 
          at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1650) 
          at android.os.Handler.dispatchMessage(Handler.java:106) 
          at android.os.Looper.loop(Looper.java:193) 
          at android.app.ActivityThread.main(ActivityThread.java:6669) 
          at java.lang.reflect.Method.invoke(Native Method) 
          at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493) 
          at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858) 
  </code></pre>
  
  <p>react-native-navigation/lib/android/app/source/etc does indeed return null in line 29 - 
  <code>private ReloadListener reloadListener = () -&gt; {};</code></p>
  
  <p>Dependencies:</p>
  
  <pre><code>engage-react@0.0.1 /Users/komara/Documents/infor-repos/EngageReact
  ├── @babel/plugin-proposal-decorators@7.2.3
  ├── @babel/runtime@7.0.0
  ├── axios@0.18.0
  ├── babel-eslint@10.0.1
  ├── babel-jest@23.6.0
  ├── babel-plugin-transform-decorators-legacy@1.3.5
  ├── babel-preset-react-native@4.0.1
  ├── eslint@5.12.0
  ├── eslint-config-airbnb@17.1.0
  ├── eslint-config-prettier@3.4.0
  ├── eslint-plugin-import@2.14.0
  ├── eslint-plugin-jsx-a11y@6.1.2
  ├── eslint-plugin-prettier@3.0.1
  ├── eslint-plugin-react@7.12.3
  ├── jest@23.6.0
  ├── metro-react-native-babel-preset@0.49.2
  ├── mobx@5.8.0
  ├── mobx-react@5.4.3
  ├── node@11.6.0
  ├── prettier@1.15.3
  ├── react@16.6.3
  ├── react-native@0.57.8
  ├── react-native-gesture-handler@1.0.12
  ├── react-native-git-upgrade@0.2.7
  ├── react-native-navigation@2.5.2
  ├── react-native-userdefaults-ios@0.1.3
  ├── react-navigation@3.0.9
  ├── react-redux@6.0.0
  ├── react-test-renderer@16.5.0
  ├── redux@4.0.1
  ├── redux-devtools@3.5.0
  ├── redux-devtools-extension@2.13.7
  ├── redux-logger@3.0.6
  ├── redux-persist@5.10.0
  ├── redux-thunk@2.3.0
  ├── remote-redux-devtools@0.5.16
  ├── schedule@0.4.0
  └── updeep@1.1.0
  </code></pre>
  
  <p>I'm guessing my dependencies are wrong, but have no idea how to fix.  </p>