[xenserver|compute] added destroy_vlan request

lib/fog/xenserver/requests/compute/destroy_vlan.rb

@@ -0,0 +1,32 @@
+module Fog
+  module Compute
+    class XenServer
+
+      class Real
+
+        # Destroy a VLAN 
+        #
+        # @see http://docs.vmd.citrix.com/XenServer/6.0.0/1.0/en_gb/api/?c=VLAN
+        #
+        def destroy_vlan( ref )
+          @connection.request(
+            {
+              :parser => Fog::Parsers::XenServer::Base.new, 
+              :method => 'VLAN.destroy'
+            }, 
+            ref
+          )
+        end
+
+      end
+
+      class Mock
+
+        def destroy_vlan( ref )
+          Fog::Mock.not_implemented
+        end
+
+      end
+    end
+  end
+end