qt 5.9.2

For being able to compile against Qt 5.9.2 I need to add 

```
'-I/usr/include/qt/QtCore/5.9.2',
'-I/usr/include/qt/QtQuickControls2',
```

in binding.gyp "cflags" property. I'm using arch linux so basically is not possible for me to downgrade without lot of work. Is this an issue of brig or arch's. Thanks