xAdded lock around the use of OnuOmciStateMap to prevent a concurrent map write issue.

I considered using a structure like sync.Map or other concurrency safe map, but those don't offer type safety like the built in map object.

Added some missing licensing and a VERSION file as Jenkins is requiring it.

Change-Id: I755709ab4678da12c7585824074a1877f98a5ea1
diff --git a/omci_pm_history_data.go b/omci_pm_history_data.go
index 15188fa..60ddd80 100644
--- a/omci_pm_history_data.go
+++ b/omci_pm_history_data.go
@@ -1,3 +1,19 @@
+/*
+ * Copyright 2018-present Open Networking Foundation
+
+ * Licensed 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.
+ */
+
 package core
 
 type PerformanceMonitoringHistoryData int