Prep v5.3 as upcoming (#368)

* Prep v5.3 as upcoming

* fix url

* update include in intro

* add 5.3 notes as toc landing page

* tidy release notes page

* fix header levels

Author: jeff-allen-mongo

snooty.toml

@@ -163,6 +163,7 @@ toc_landing_pages = [
    "/release-notes/5.0",
    "/release-notes/5.1",
    "/release-notes/5.2",
+   "/release-notes/5.3",
    "/replication",
    "/security",
    "/sharding",

source/includes/fact-mongodb-intro.rst

@@ -5,4 +5,4 @@ query language, and provides operational and administrative
 considerations and procedures as well as a comprehensive reference
 section.
 
-.. include:: /includes/rapid-release-short.rst
+.. include:: /includes/in-dev.rst

source/index.txt

@@ -18,7 +18,7 @@ What is MongoDB?
    .. button:: Get started with MongoDB Atlas
       :uri: https://www.mongodb.com/cloud?tck=docs_server
 
-   .. include:: /includes/rapid-release.rst
+   .. include:: /includes/in-dev.rst
 
 .. image:: /images/hero.png
    :alt: Homepage hero image

source/release-notes.txt

@@ -9,23 +9,45 @@ Always install the latest, stable version of MongoDB. See
 See the following release notes for an account of the changes in major
 versions. Release notes also include instructions for upgrade.
 
+Atlas Rapid Releases
+~~~~~~~~~~~~~~~~~~~~
+
+.. important::
+
+   Rapid releases are only supported for MongoDB Atlas. Rapid releases
+   are not supported for use on-premises. For more information, see
+   :ref:`release-version-numbers`.
+
+Upcoming Atlas Rapid Release
+````````````````````````````
+
+(*5.3-series*)
+
+:doc:`/release-notes/5.3`
+
+.. include:: /includes/in-dev.rst
+
+.. toctree::
+   :maxdepth: 1
+   :hidden:
+
+   /release-notes/5.3
+
 Current Atlas Rapid Release
-~~~~~~~~~~~~~~~~~~~~~~~~~~~
+```````````````````````````
 
 (*5.2-series*)
 
 :doc:`/release-notes/5.2`
 
-.. include:: /includes/rapid-release.rst
-
 .. toctree::
    :maxdepth: 1
    :hidden:
 
    /release-notes/5.2
 
 Previous Atlas Rapid Releases
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+`````````````````````````````
 
 (*5.1-series*)