Blender Git Loki

Cycles: disable progressive refine if denoising or save buffers is used.

Progressive refine undoes memory saving from save buffers, so enabling
both does not make much sense. Previously enabling progressive refine
would disable denoising, but it should be the other way around since
denoise actually affects the render result.

Includes some code refactor for progressive refine render buffers, and
avoids recomputing tiles for each progressive sample.