This process is somewhat involved. I may write notes about how to do this well in the future.
==== Enabling LaTeX ====
# Install the [https://www.mediawiki.org/wiki/Extension:Math Math] extension to the <code>extensions</code> directory
# Change to the <code>origin/REL1_31</code> branch
# Run the update script: <code>sudo php maintenance/update.php</code>