idea for this library partly based on oryginal wemos code from:
https://github.com/wemos/WEMOS_Matrix_LED_Shield_Arduino_Library
with a few mods and additions like scroll, letters, icons, display flip and improvements of speed.
Some parts of code is based on solutions from websites.
Lib still under development (maybe forever), please comment out #define MATRIXDEBUG for normal usage
2017-2019 Reaper7