[vcloud_director] Add power_off for vm

lib/fog/vcloud_director/compute.rb

@@ -98,6 +98,7 @@ module Fog
       request :put_metadata_value
       request :delete_metadata
       request :post_vm_poweron
+      request :post_vm_poweroff
       request :get_request # this is used for manual testing
       request :get_href    # this is used for manual testing
       request :get_vms_by_metadata

lib/fog/vcloud_director/models/compute/vm.rb

@@ -48,6 +48,11 @@ module Fog
           service.process_task(response.body)
         end
 
+        def power_off
+          response = service.post_vm_poweroff(id)
+          service.process_task(response.body)
+        end
+
         def tags
           requires :id
           service.tags(:vm => self)

lib/fog/vcloud_director/requests/compute/post_vm_poweroff.rb

@@ -0,0 +1,18 @@
+module Fog
+  module Compute
+    class VcloudDirector
+      class Real
+
+        def post_vm_poweroff(vm_id)
+
+          request(
+            :expects  => 202,
+            :method   => 'POST',
+            :parser => Fog::ToHashDocument.new,
+            :path     => "vApp/#{vm_id}/power/action/powerOff"
+          )
+        end
+      end
+    end
+  end
+end