Checked in missing license header

docs/en-US/add-clusters-ovm.xml

@@ -3,6 +3,25 @@
 <!ENTITY % BOOK_ENTITIES SYSTEM "cloudstack.ent">
 %BOOK_ENTITIES;
 ]>
+
+<!-- Licensed to the Apache Software Foundation (ASF) under one
+    or more contributor license agreements.  See the NOTICE file
+    distributed with this work for additional information
+    regarding copyright ownership.  The ASF licenses this file
+    to you under the Apache License, Version 2.0 (the
+    "License"); you may not use this file except in compliance
+    with the License.  You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+    Unless required by applicable law or agreed to in writing,
+    software distributed under the License is distributed on an
+    "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+    KIND, either express or implied.  See the License for the
+    specific language governing permissions and limitations
+    under the License.
+-->
+
 <section id="add-clusters-ovm">
     <title>Add Cluster: OVM</title>
     <para>To add a Cluster of hosts that run Oracle VM (OVM):</para>