Doc - Add info about layouts to the example

Reviewed-by: Niels Weber

doc/examples/batteryindicator/main.cpp

@@ -5,11 +5,14 @@ int main(int argc, char *argv[])
 {
     QApplication a(argc, argv);
     BatteryIndicator w;
+
+//! [0]
 #if defined(Q_WS_S60)
     w.showMaximized();
 #else
     w.show();
 #endif
+//! [0]
 
     return a.exec();
 }