DOCSP-17867 node 4.1 release (#222)

* updated compatibility table and what's new page

Author: kyuan-mongodb

source/includes/mongodb-compatibility-table-node.rst

@@ -14,6 +14,17 @@
      - MongoDB 3.0
      - MongoDB 2.6
 
+   * - 4.1
+     - ✓
+     - ✓
+     - ✓
+     - ✓
+     - ✓
+     - ✓
+     - ✓
+     - ✓
+     - ✓
+
    * - 4.0
      - ✓
      - ✓

source/whats-new.txt

@@ -12,9 +12,20 @@ What's New
 
 Learn what's new in:
 
+* :ref:`Version 4.1 <version-4.1>`
 * :ref:`Version 4.0 <version-4.0>`
 * :ref:`Version 3.6 <version-3.6>`
 
+.. _version-4.1:
+
+What's New in 4.1
+-----------------
+
+New features of the 4.1 Node.js driver release include:
+
+- Added support for load balancer support to use in the beta :atlas:`Serverless platform </choose-database-deployment-type/>`
+- Added support for the ``advanceClusterTime()`` method to determine if the ``ClientSession`` should update its cluster time
+
 .. _version-4.0:
 
 What's New in 4.0