add release notes for the ddk

Author: Wolfgang Manousek

articles/cognitive-services/Speech-Service/devices-sdk-release-notes.md

@@ -0,0 +1,25 @@
+---
+title: Cognitive Services Speech Devices SDK Documentation
+description: Release notes - what has changed in the most recent releases
+titleSuffix: "Microsoft Cognitive Services"
+services: cognitive-services
+author: wsturman
+
+ms.service: cognitive-services
+ms.component: speech-service
+ms.topic: article
+ms.date: 08/07/2018
+ms.author: gracez
+---
+
+# Release notes of Speech Devices SDK
+
+## Cognitive Services Speech Devices SDK 0.5.0: 2018-Aug release
+
+* Improved the accuracy of speech recognition by fixing a bug in the audio processing code.
+* Updated the [Speech SDK](https://docs.microsoft.com/azure/cognitive-services/speech-service/speech-sdk-reference) component to version 0.5.0, see its 
+[Release notes](releasenotes.md#cognitive-services-speech-sdk-050-2018-july-release).
+
+## Cognitive Services Speech Devices SDK 0.2.12733: 2018-May release
+
+The first public preview release of the Cognitive Services Speech Devices SDK.

articles/cognitive-services/Speech-Service/toc.yml

@@ -161,6 +161,12 @@
       href: third-party-notices.md
   - name: Speech Devices SDK
     items:
+    - name: Download 
+      href: 'get-speech-devices-sdk.md#download-the-speech-devices-sdk'
+    - name: Samples
+      href: https://github.com/Azure-Samples/Cognitive-Services-Speech-Devices-SDK 
+    - name: Release notes
+      href: devices-sdk-release-notes.md
     - name: License
       href: speech-devices-sdk-license.md
       displayName: roobo, speech devices sdk