Android TV: Allow the app to be launched from an Android TV launcher.

Source/Android/app/src/main/AndroidManifest.xml

@@ -21,6 +21,7 @@
             <intent-filter>
                 <action android:name="android.intent.action.MAIN"/>
 
+                <category android:name="android.intent.category.LEANBACK_LAUNCHER"/>
                 <category android:name="android.intent.category.LAUNCHER"/>
             </intent-filter>
         </activity>