* Don't force rendering in File::getThumbnail(). The old code (pre-filerepo) required...

* Don't force rendering in File::getThumbnail(). The old code (pre-filerepo) required rendering to be forced all the time, the new code is much smarter about when to render and doesn't need rendering to be forced. Forcing rendering causes non-scaler servers to be used for scaling.
* Use File::transform() in the core instead of the deprecated File::getThumbnail().