Make I2C handling work for other platforms, eg ESP32, Arduino

[Strooom]

[Strooom]

I've included some conditional compilation in order to include the special I2C (i2c_t3.h) for Teensy3.x OR the standard Wire.h for other MCUs. However there remains one issue to be solved : the length of the Rx and Tx buffers used in Wire.h
Standard this buffer is 259 bytes for Teensy's i2c_t3.h. For Wire.h it is 32 bytes (or more for ESP32 implementation).
We need to be sure it is 259 bytes in all cases.
This is not required for the Control messages, as they are typically not longer than 32 bytes, but it will become required when we start reading/writing data from/to the Tags, which will use maximum length messages.