Changes the "Motors Off" command from M18 to M84 for compatibility with Repetier Firmware.

A plugin to intercept the gcode command M18 during the queueing stage and rewrite it as M84 before sending it to the printer (for compatibility with the Repetier line of firmware).

Note: Because this plugin intercepts the code during the queueing stage, that also includes manual gcode entry. Entering M18 in the terminal tab will also result in it being send to the printer as M84.