Fix hit detection bug for player

`Player` wasn't having hit detection because of the mirrored `scaleX`.

It might be a bug in Futile, so I just modified the
`GetTextureRectRelativeToContainer()` method in order to "fix" it. An
issue has been filed
[here](https://github.com/MattRix/Futile/issues/215).
modify FSprite to fix hit detection
Change background to new art