Understanding NMS and nms_postprocess

Hi @sylvain.fabre,
The postprocessing section of the YAML file is necessary just for the Hailo Model Zoo evaluation pipeline. The hailomz tool needs to know whether the NMS is already part of HailoRT (nms: true), or if it needs to use Model Zoo postprocessing.
In this case is set to true, since the nms_postprocess command has been added to the model script.