[nancy] grele - Add operating system release

data/grid5000/sites/nancy/clusters/grele/nodes/grele-1.json

data/grid5000/sites/nancy/clusters/grele/nodes/grele-10.json

data/grid5000/sites/nancy/clusters/grele/nodes/grele-11.json

data/grid5000/sites/nancy/clusters/grele/nodes/grele-12.json

data/grid5000/sites/nancy/clusters/grele/nodes/grele-13.json

data/grid5000/sites/nancy/clusters/grele/nodes/grele-14.json

data/grid5000/sites/nancy/clusters/grele/nodes/grele-2.json

data/grid5000/sites/nancy/clusters/grele/nodes/grele-3.json

data/grid5000/sites/nancy/clusters/grele/nodes/grele-4.json

data/grid5000/sites/nancy/clusters/grele/nodes/grele-5.json

data/grid5000/sites/nancy/clusters/grele/nodes/grele-6.json

data/grid5000/sites/nancy/clusters/grele/nodes/grele-7.json

data/grid5000/sites/nancy/clusters/grele/nodes/grele-8.json

data/grid5000/sites/nancy/clusters/grele/nodes/grele-9.json

grid5000-all.json

input/grid5000/sites/nancy/clusters/grele/grele.yaml