Blender Git Loki

* Fix for bug # 7396 "Refraction Pass Being added to combined when not told to"

For the record, I think the way these reflection and refraction passes are handled (as a difference against the diffuse pass) is not very useful - especially if you want to do colour corrections, blurring, etc. It would be much more practical for the passes to contain the ray result returned by the raytrace...