New sensor as RealExpression of the MSL with ColorScale

The RealExpression of the MSL is very useful and it would be probably interesting to develop a ThermoSysPro version (with the .signal so that it would be easy to plug to TSP I&C).

It could also be developed with a color scale feature to animate the simulation (imagine seeing the color of the sensors, in different location of the model, moving accordingly to the temperature or pressure or whatever).