Muli-color Graphing routines written

 Added functionality to graph in multiple colors.

Log Graphing Added

Added the ability to scale the graph to logarithmic functions.  This allows extremely large scales to be plotted in smaller areas.  

This can be expanded to create log-linear and log-log graphs.

Graph Calculations abstracted

In drawing the graph (lacking any C++ graphing libraries for the RPi) I had to scale the measurements to fit in the graph area. I abstracted the calculation so it can be used for any size graph with any span.  This will allow the graph the be zoomed in to in future enhancements

Charting extended

Charting is now working on both the x-axis and the y-axis. 

Scaling to temperature and pressure has been completed. 

Charting across both chambers has been completed.

Charting now working

I have added out-of-band charting functions to the code that will allow me to chart in GTK:DrawingAreas without having to trigger an event. 

It sounds simple, but apparently GTK::Draw is not really robust when it comes to just drawing a simple line. They prefer you create and event handler and have the event handler draw the line when the event is triggered. 

 Unfortunately, Unix, C++, RaspberryPi combination is the perfect storm for zero interactive grahping support.

GUI now functioning

After a few small setbacks, I have reloaded the Operating System and Integrated Development Environment on the Raspberry Pi. I was then able to add the GTKMM GUI libraries in the IDE. Now I have a functioning GU?I for the Freeze dryer project up and running. I am running Raspian OS with the Codelite IDE and the GTKMM GUI library. Once the GUI was up it was fairly easy to import all of the old Command Line Interface libraies for the sensors and relays. They were designed from the ground up to be ported to a GUI, so it went pretty smooth.