Crashes with updated libraries (Clarify required library versions in docs)

[z-l-p]

I just spent hours trying to compile the V2 code in 2021 (Arduino IDE 1.8.9). Much has changed since 2019, and compiling with current library versions will result in a crashed Arduino (no display at startup, etc). Most open issues seem to be traceable to this. My solution was to look back through the releases of all required libraries to find the ones that were contemporary in March 2019 when the initial commit was made. I had success with the versions below. (Others might work too, but I got tired of trying.)

• Arduino PID Library: v1.1.1
• Adafruit MAX31856 Library: v1.0.3
• Adafruit SSD1306 Library: v1.2.9
• Adafruit GFX Library: v1.4.8

NOTE: The Arduino IDE library manager doesn't seem to roll back to previous versions gracefully. It's best to delete the folders for any existing versions before using the library manager to download the old versions.

Maybe lib version requirements could be added to the README or the code comments?

[szlovak]

What I have found out also is , that PID settings are totally different from these that are already loaded in FW that comes with board. I wanted only to change default values , reflow phase was too fast in my oven. After loading sketch nothing matches what was before, none of three phases.