A note about installing developer version from Docker.

The last Docker release was 2 years ago. Folks might want
to use Docker to get a more recent version. Here is how.

Author: rwest

documentation/source/users/rmg/installation/index.rst

@@ -39,6 +39,12 @@ For users unfamiliar with bash or Linux, we recommend looking at
 `Terminal vs File Manager <https://www.guru99.com/terminal-file-manager.html>`_, and
 `Must Know Linux/Unix Commands <https://www.guru99.com/must-know-linux-commands.html>`_.
 
+.. NOTE::
+    The instructions above are for the release version 3.2.0 of RMG-Py (August 2023).
+    If you want to use the latest development version, you can replace the version number in the docker pull command with "latest" or omit it entirely.
+    For example, you can run ``docker pull reactionmechanismgenerator/rmg:latest`` or ``docker pull reactionmechanismgenerator/rmg`` to get the latest development version corresponding to `here <https://github.com/ReactionMechanismGenerator/RMG-Py/commits/main/>`_.
+    Be sure to also change the version number in the docker run commands to match the version you pulled.
+    A full list of available docker images can be found at `Docker Hub <https://hub.docker.com/r/reactionmechanismgenerator/rmg/tags>`_.
 
 Alternative Install: Binary Installation Using Anaconda
 ===========================================================