[nancy][kwollect]add conf for grdix, sgrdix & minimal conf for gres

data/grid5000/accesses/refrepo.json

data/grid5000/sites/nancy/clusters/grdix/grdix.json

data/grid5000/sites/nancy/clusters/gres/gres.json

data/grid5000/sites/nancy/network_equipments/sgrdix.json

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

input/grid5000/sites/nancy/clusters/grdix/grdix_metrics.yaml

input/grid5000/sites/nancy/networks/sgrdix.yaml