HBASE-22698 [hbase-connectors] Add license header to README.md

Signed-off-by: Peter Somogyi <psomogyi@apache.org>
diff --git a/spark/hbase-spark/README.md b/spark/hbase-spark/README.md
index 4fe448a..315fa64 100644
--- a/spark/hbase-spark/README.md
+++ b/spark/hbase-spark/README.md
@@ -1,3 +1,21 @@
+<!---
+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.
+-->
+
 ##ON PROTOBUFS
 This maven module has core protobuf definition files ('.protos') used by hbase
 Spark that ship with hbase core including tests.