Update README

Author: doubletao318

README.md

@@ -1,5 +1,17 @@
-# OpenStack_Driver
-Cinder and Manila drivers for Huawei storage.
+# Huawei OpenStack Cinder Driver and Manila Driver
+## Overview
+Huawei Cinder driver is used to adapt OpenStack and SAN storage which in order to 
+provide LUNs to VMs. In addition, cinder driver also provides a series of LUN-related services, 
+such as snapshots, retype, manage-existing, replication, hypermetro and QoS. 
+Otherwise, the Manila driver is used to adapt OpenStack and NAS storage which mount the 
+filesystem directly to the VMs. Also, manila driver support snapshot, replication, hypermetro, 
+QoS and so on.
 
-Cinder driver internal version: 2.2.5
-Manila driver internal version: 2.2.3
+## Compatibility Matrix
+The strategies of Huawei Cinder Driver and Manila Driver are consistent with the OpenStack community, we support the 
+latest 6 versions. **For other versions, it can be used but no longer maintained.**
+
+| OpenStack |Ocata|Pike|Queens|Rocky|Stein|Train|
+|---|---|---|---|---|---|---|
+|Cinder Driver|√|√|√|√|√|√|
+|Manila Driver|√|√|√|√|√|√|