Fix lint errors

Author: hannesa2

app/src/main/res/menu/main.xml

@@ -1,9 +1,10 @@
-<menu xmlns:android="http://schemas.android.com/apk/res/android" >
+<menu xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:android="http://schemas.android.com/apk/res/android" >
 
     <item
         android:id="@+id/action_settings"
         android:orderInCategory="100"
-        android:showAsAction="never"
-        android:title="@string/action_settings"/>
+        android:title="@string/action_settings"
+        app:showAsAction="never" />
 
 </menu>