Selecting GPU devices in utils.py and run.sh

[vadimkantorov]

I found a useful tutorial: https://b3d.interplanety.org/en/render-from-console-only-on-the-specified-gpu-devices-2/

This is useful for big GPU machines which may be shared by multiple people, specifying the devices is useful. Btw does Blender respect CUDA_VISIBLE_DEVICES / NVIDIA_VISIBLE_DEVICES?