Tu as juste à taper en ssh les deux commandes de @naboleo.
sudo wget https://raw.githubusercontent.com/domotruc/jMQTT/fd3b76745f3b791503c418c6aae085c4c1764f82/desktop/php/jMQTT.php -O /var/www/html/plugins/jMQTT/desktop/php/jMQTT.php
sudo wget https://raw.githubusercontent.com/domotruc/jMQTT/fd3b76745f3b791503c418c6aae085c4c1764f82/desktop/js/jMQTT.js -O /var/www/html/plugins/jMQTT/desktop/js/jMQTT.js