Mcmod file fix + Remote Thermometer textures

I'm not advanced enough in Java to fully understand how the Remote Thermometer renderer code works, but since we're upgrading the textures from x16 to x32, it might be necessary to rewrite it. Assuming that, I went for another display for this machine, and once we have a working wersion, I'll code the renderer myself if nobody did it before me.

In short : the initial state of the machine is off. The first half of the slider texture is how the screen will be rendered when on, and the second half is the full slider, which should be gradually displayed depending of the heat of the generator. There's a little helper on the slider texture itself.