Use non-compressed textures in example

Not all drivers/devices support all compressed texture formats, so
restore the old version of this example that uses jpgs. Copy the
current version to the manual tests directory.

Change-Id: I2f3f013f915f16aa6903ffef195c942b1ec23306
Reviewed-by: Laszlo Agocs <laszlo.agocs@qt.io>
Reviewed-by: Eirik Aavitsland <eirik.aavitsland@qt.io>
(cherry picked from commit 9b402cdf)