provide a more general example with more explanation about esp32-twai-can

[handmade0octopus]

Few notes there.

All functions should have definitions before they are called - meaning loop and setup should be the last ones to call.

This is not an issue on Arduino IDE but it's good convention to keep in mind as platformio won't be happy about it and in general it's good practice.

You can also format your code a bit by using ```cpp after code block.

Example:

// easy to use helper-function for non-blocking timing
boolean TimePeriodIsOver (unsigned long &startOfPeriod, unsigned long TimePeriod) {
  unsigned long currentMillis  = millis();
  if ( currentMillis - startOfPeriod >= TimePeriod ) {
    // more time than TimePeriod has elapsed since last time if-condition was true
    startOfPeriod = currentMillis; // a new period starts right here so set new starttime
    return true;
  }
  else return false;            // actual TimePeriod is NOT yet over
}

I also prefer formatting using prtinf instead of chaining prints - this gives user ability to learn how printf works.

Thank you for idea though. I will try to make it more clear to users but I am not sure which part is confusing there and I tried to keep example short.