[grenoble][troll] Add Troll cluster

...grid5000/sites/grenoble/clusters/troll/nodes/troll-1.json

...grid5000/sites/grenoble/clusters/troll/nodes/troll-2.json

...grid5000/sites/grenoble/clusters/troll/nodes/troll-3.json

...grid5000/sites/grenoble/clusters/troll/nodes/troll-4.json

data/grid5000/sites/grenoble/clusters/troll/troll.json

data/grid5000/sites/grenoble/network_equipments/gw.json

...grid5000/sites/grenoble/clusters/troll/nodes/troll-1.yaml

...grid5000/sites/grenoble/clusters/troll/nodes/troll-2.yaml

...grid5000/sites/grenoble/clusters/troll/nodes/troll-3.yaml

...grid5000/sites/grenoble/clusters/troll/nodes/troll-4.yaml

input/grid5000/sites/grenoble/clusters/troll/troll.yaml

...rid5000/sites/grenoble/clusters/troll/troll_ipv6.yaml.erb

input/grid5000/sites/grenoble/networks/gw.yaml

input/grid5000/vlans.yaml

lib/refrepo/net_names_mapping.yaml