Mqtt5 General Avalibility (#666)

* remove dev preview

* submodule

* update submodule

documents/MQTT5_Userguide.md

@@ -1,5 +1,4 @@
 # Table of Contents
-* [Developer Preview Disclaimer](#developer-preview-disclaimer)
 * [Introduction](#introduction)
 * [What's Different? (relative to the MQTT311 implementation)](#what-s-different---relative-to-the-mqtt311-implementation-)
     + [Major changes](#major-changes)
@@ -24,12 +23,6 @@
         - [Publish](#publish)
 * [MQTT5 Best Practices](#mqtt5-best-practices)
 
-# Developer Preview Disclaimer
-
-MQTT5 support is currently in **developer preview**.  We encourage feedback at all times, but feedback during the preview window is especially valuable in shaping the final product.  During the preview period we may make backwards-incompatible changes to the public API, but in general, this is something we will try our best to avoid.
-
-The MQTT5 client cannot yet be used with the AWS IoT MQTT services (Shadow, Jobs, Identity).  This is a shortcoming that we hope to address in the near future.
-
 # Introduction
 
 This user guide is designed to act as a reference and guide for how to use MQTT5 with the CPP SDK, covering what MQTT5 is and some essential knowledge required to effectively use of MQTT5 within the CPP SDK.

samples/mqtt5/mqtt5_pubsub/README.md

@@ -8,8 +8,6 @@ for AWS IoT to send and receive messages through an MQTT connection using MQTT5.
 
 MQTT5 introduces additional features and enhancements that improve the development experience with MQTT. You can read more about MQTT5 in the C++ V2 SDK by checking out the [MQTT5 user guide](../../../documents/MQTT5_Userguide.md).
 
-Note: MQTT5 support is currently in **developer preview**. We encourage feedback at all times, but feedback during the preview window is especially valuable in shaping the final product. During the preview period we may make backwards-incompatible changes to the public API, but in general, this is something we will try our best to avoid.
-
 Your IoT Core Thing's [Policy](https://docs.aws.amazon.com/iot/latest/developerguide/iot-policies.html) must provide privileges for this sample to connect, subscribe, publish, and receive. Below is a sample policy that can be used on your IoT Core Thing that will allow this sample to run as intended.
 
 <details>

samples/mqtt5/mqtt5_shared_subscription/README.md

@@ -8,8 +8,6 @@ for AWS IoT to send and receive messages over a MQTT5 connection using a shared
 
 MQTT5 introduces additional features and enhancements that improve the development experience with MQTT. You can read more about MQTT5 in the C++ V2 SDK by checking out the [MQTT5 user guide](../../../documents/MQTT5_Userguide.md).
 
-Note: MQTT5 support is currently in **developer preview**. We encourage feedback at all times, but feedback during the preview window is especially valuable in shaping the final product. During the preview period we may make backwards-incompatible changes to the public API, but in general, this is something we will try our best to avoid.
-
 [Shared Subscriptions](https://docs.aws.amazon.com/iot/latest/developerguide/mqtt.html#mqtt5-shared-subscription) allow IoT devices to connect to a group where messages sent to a topic are then relayed to the group in a round-robin-like fashion. This is useful for distributing message load across multiple subscribing MQTT5 clients automatically. This is helpful for load balancing when you have many messages that need to be processed.
 
 Shared Subscriptions rely on a group name/identifier, which tells the MQTT5 broker/server which IoT devices to treat as a group for message distribution. This is done when subscribing by formatting the subscription topic like the following: `$share/<ShareName>/<TopicFilter>`.