DOCSP-14426 whats new (#169)

* added What's New page

Author: kyuan-mongodb

source/fundamentals/authentication/mechanisms.txt

@@ -122,6 +122,7 @@ in the following sample code.
    SCRAM </release-notes/3.0-scram/>`, any ``MONGODB-CR`` user
    authentication requests fail.
 
+.. _mongodb-aws: 
 
 ``MONGODB-AWS``
 ---------------

source/index.txt

@@ -19,7 +19,7 @@ MongoDB Node Driver
   /faq
   /issues-and-help
   /compatibility
-
+  /whats-new
 
 Introduction
 ------------
@@ -102,3 +102,8 @@ Compatibility
 -------------
 The :doc:`Compatibility </compatibility>` section shows compatibility charts
 with the Node.js language and the MongoDB server versions.
+
+What's New
+----------
+The :doc:`What's New </whats-new>` section shows new features and
+changes in each version.

source/whats-new.txt

@@ -0,0 +1,41 @@
+==========
+What's New
+==========
+
+.. default-domain:: mongodb
+
+.. contents:: On this page
+   :local:
+   :backlinks: none
+   :depth: 1
+   :class: singlecol
+
+Learn what's new in:
+
+* :ref:`Version 4.0 <version-4.0>`
+* :ref:`Version 3.6 <version-3.6>`
+
+.. _version-4.0:
+
+What's New in 4.0
+-----------------
+
+New features of the 4.0 Node.js driver release include:
+
+.. _version-3.6:
+
+What's New in 3.6
+-----------------
+
+New features of the 3.6 Node.js driver release include:
+
+- Added support for the :ref:`MONGODB-AWS <mongodb-aws>` authentication mechanism using Amazon Web Services (AWS) Identity and Access Management (IAM) credentials
+- Added support for Online Certificate Status Protocol (OCSP)
+- The :node-api:`find()<Collection.html#find>` method supports ``allowDiskUse()`` for sorts that require too much memory to execute in RAM
+- The :ref:`update() <updateDocuments>` and :ref:`replaceOne() <replacementDocument>` methods support index hints
+- A reduction in recovery time for topology changes and failover events
+- Improvements in validation testing for the default :manual:`writeConcern </reference/write-concern/>`
+- Authentication requires fewer round trips to the server, resulting in faster connection setup
+- Shorter Salted Challenge Response Authentication Mechanism (:manual:`SCRAM </core/security-scram/>`) conversations
+- Ability to create collections and indexes for multiple document transactions
+- Running validation for a collection in the background