Add release notes and fix docs

Add release notes for SMS
Fix other docs issues in SMS

Issue-ID: AAF-185
Change-Id: Ib3860018229b61942ab8a48cfdafe0b3f21ceed1
Signed-off-by: Kiran Kamineni <kiran.k.kamineni@intel.com>
diff --git a/docs/architecture.rst b/docs/architecture.rst
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+.. This work is licensed under a Creative Commons Attribution 4.0 International License.
+.. http://creativecommons.org/licenses/by/4.0
+.. Copyright 2018 Intel Corporation, Inc
+
+Architecture
+============
+
+This project aims at the Storage of sensitive information such as passwords, username, and tokens.
+
+**Current state and gaps**
+
+Many services in ONAP use password based authentication. Eg: Database servers, publish/subscribe brokers etc.
+Passwords are stored in plain text files in many services.
+With multiple instances of these services, the attack surface area becomes very big.
+Hence there is a need to ensure that attack surface related to password exposure is reduced.
+
+**Requirement:**
+
+Need for Secure Secret Management.
+Services are expected to get the secret only on needed basis using secret reference and remove the secrets once they are used up.
+
+**Secret Service High Level Flow Diagram**
+
+.. image:: sms_high_level.png
+   :width: 900px
+   :height: 400px
+   :alt: SMS Flow Diagram