DOCS-10978: where to download latest mongodb

Author: kay-kim

source/index.txt

@@ -19,7 +19,9 @@ The MongoDB |version| Release Candidate Manual
    :class: note
 
    For new features in MongoDB 3.6 Release Candidate, see
-   :doc:`/release-notes/3.6`.
+   :doc:`/release-notes/3.6`. To download the MongoDB 3.6 Release
+   Candidate, go to the `MongoDB Download Center
+   <https://www.mongodb.com/download-center?jmp=docs#development>`_
 
 Welcome to the MongoDB |version| Manual! MongoDB is an open-source,
 document database designed for ease of development and scaling. The