[lyon] Add /pdus/ directory to ref API for Lyon (#5438)

data/grid5000/sites/lyon/pdus/wattmetre.json

+{
+  "model": "",
+  "sensors": [
+    {
+      "power": {
+        "per_outlets": true,
+        "wattmetre": {
+          "available": true,
+          "unit": "W",
+          "www": {
+            "url": "http://wattmetre.lyon.grid5000.fr/GetWatts-json.php"
+          }
+        }
+      }
+    }
+  ],
+  "type": "pdu",
+  "uid": "wattmetre",
+  "vendor": "OmegaWatt"
+}
\ No newline at end of file

generators/input/sites/lyon/pdus.rb

+site :lyon do |site_uid|
+  pdu "wattmetre" do |pdu_uid|
+    vendor "OmegaWatt"
+    model ""
+    sensors [
+      {
+        :power => {
+          :per_outlets => true,
+          :wattmetre => {
+            :available => true,
+            :www => { :url => 'http://wattmetre.lyon.grid5000.fr/GetWatts-json.php' },
+            :unit => "W",
+          }
+        }
+      }
+    ]
+  end
+end