android: Set target SDK to 17 (Android 4.2)

src/frontends/android/AndroidManifest.xml

@@ -20,7 +20,7 @@
     android:versionCode="8"
     android:versionName="1.2.0" >
 
-    <uses-sdk android:minSdkVersion="14" />
+    <uses-sdk android:minSdkVersion="14" android:targetSdkVersion="17" />
 
     <uses-permission android:name="android.permission.INTERNET" />
     <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />