Android Refactor: GameGridActivity is now MainActivity, and uses a Toolbar that reacts to the game grid scrolling.

Source/Android/app/src/main/res/menu/menu_game_grid.xml

@@ -1,14 +1,15 @@
 <?xml version="1.0" encoding="utf-8"?>
-<menu xmlns:android="http://schemas.android.com/apk/res/android">
+<menu xmlns:android="http://schemas.android.com/apk/res/android"
+      xmlns:app="http://schemas.android.com/apk/res-auto">
     <item
         android:id="@+id/menu_refresh"
         android:title="@string/grid_menu_refresh"
         android:icon="@drawable/ic_refresh"
-        android:showAsAction="ifRoom"/>
+        app:showAsAction="ifRoom"/>
     <item
         android:id="@+id/menu_settings"
         android:title="@string/grid_menu_settings"
         android:icon="@drawable/ic_settings"
-        android:showAsAction="ifRoom"/>
+        app:showAsAction="ifRoom"/>
 
 </menu>