DOCSP-27916: link GH docs (#78)

* DOCSP-27916: link GH docs

Author: Chris Cho

source/index.txt

@@ -6,6 +6,7 @@ MongoDB C# Driver
 
 .. toctree::
 
+   /previous-versions
    /quick-start
    /quick-reference
    /usage-examples
@@ -19,11 +20,16 @@ MongoDB C# Driver
 Introduction
 ------------
 
-Welcome to the documentation site for the official {+driver-long+}. 
-You can add the driver to your application to work with MongoDB in {+language+}. 
+Welcome to the documentation site for the official {+driver-long+}.
+You can add the driver to your application to work with MongoDB in {+language+}.
 Download the driver using `NuGet <https://www.nuget.org/packages/MongoDB.Driver>`__, or set up a runnable
 project by following our :ref:`Quick Start guide <csharp-quickstart>`.
 
+Previous Versions
+-----------------
+
+For documentation on versions of the driver v2.18 and earlier, see the :ref:`csharp-previous-versions` section.
+
 Quick Start
 -----------
 
@@ -77,7 +83,7 @@ for each MongoDB Server version, see :ref:`csharp-compatibility-tables`.
 What's New
 ----------
 
-For a list of new features and changes in each version, see the :doc:`What's New </whats-new>` 
+For a list of new features and changes in each version, see the :doc:`What's New </whats-new>`
 section.
 
 Issues & Help

source/previous-versions.txt

@@ -0,0 +1,29 @@
+.. _csharp-previous-versions:
+
+=================
+Previous Versions
+=================
+
+The following links direct you to documentation for previous versions of the
+driver.
+
+- `Version 2.18 <https://mongodb.github.io/mongo-csharp-driver/2.18/>`__
+- `Version 2.17 <https://mongodb.github.io/mongo-csharp-driver/2.17/>`__
+- `Version 2.16 <https://mongodb.github.io/mongo-csharp-driver/2.16/>`__
+- `Version 2.15 <https://mongodb.github.io/mongo-csharp-driver/2.15/>`__
+- `Version 2.14 <https://mongodb.github.io/mongo-csharp-driver/2.14/>`__
+- `Version 2.13 <https://mongodb.github.io/mongo-csharp-driver/2.13/>`__
+- `Version 2.12 <https://mongodb.github.io/mongo-csharp-driver/2.12/>`__
+- `Version 2.11 <https://mongodb.github.io/mongo-csharp-driver/2.11/>`__
+- `Version 2.10 <https://mongodb.github.io/mongo-csharp-driver/2.10/>`__
+- `Version 2.9 <https://mongodb.github.io/mongo-csharp-driver/2.9/>`__
+- `Version 2.8 <https://mongodb.github.io/mongo-csharp-driver/2.8/>`__
+- `Version 2.7 <https://mongodb.github.io/mongo-csharp-driver/2.7/>`__
+- `Version 2.6 <https://mongodb.github.io/mongo-csharp-driver/2.6/>`__
+- `Version 2.5 <https://mongodb.github.io/mongo-csharp-driver/2.5/>`__
+- `Version 2.4 <https://mongodb.github.io/mongo-csharp-driver/2.4/>`__
+- `Version 2.3 <https://mongodb.github.io/mongo-csharp-driver/2.3/>`__
+- `Version 2.2 <https://mongodb.github.io/mongo-csharp-driver/2.2/>`__
+- `Version 2.1 <https://mongodb.github.io/mongo-csharp-driver/2.1/>`__
+- `Version 2.0 <https://mongodb.github.io/mongo-csharp-driver/2.0/>`__
+- `Version 1.11 <https://mongodb.github.io/mongo-csharp-driver/1.11/>`__