Add Nova scenario to list hypervisors

Benchmarks the 'nova list-hypervisors' command.

Change-Id: I64243de369ac02afb7dcf246b3d8e28d7c43d172

rally-jobs/rally.yaml

@@ -1336,6 +1336,18 @@
         failure_rate:
           max: 0
 
+  NovaHypervisors.list_hypervisors:
+    -
+      args:
+        detailed: True
+      runner:
+        type: "constant"
+        times: 5
+        concurrency: 2
+      sla:
+        failure_rate:
+          max: 0
+
   VMTasks.boot_runcommand_delete:
     -
       args:

samples/tasks/scenarios/nova/list-hypervisors.json

@@ -0,0 +1,14 @@
+{
+  "NovaHypervisors.list_hypervisors": [
+    {
+      "runner": {
+        "type": "constant",
+        "concurrency": 2,
+        "times": 10
+      },
+      "args": {
+        "detailed": true
+      }
+    }
+  ]
+}

samples/tasks/scenarios/nova/list-hypervisors.yaml

@@ -0,0 +1,9 @@
+---
+  NovaHypervisors.list_hypervisors:
+    -
+      args:
+        detailed: True
+      runner:
+        type: "constant"
+        times: 10
+        concurrency: 2