Updtead core to v3.1.3

Updated core to v3.1.2

Updated core to support MMOD

Removed Units dependency

Added default constructor and a Config method to configure the sensor

Updated to use the Units library for PSI to PA conversion

Merging Ams5812 and Ams5812-arduino

Removed the old GPLV3 license file. This is a MIT licensed library.

Updated std::size_t to int to support microcontrollers without access…

… to STL

Updated to match our AMS-5812 library for flight software