Smartcard Lib for Arduino compat. boards

Smartcard access lib for Arduino based boards connected directly to a smartcard.

This is currently a work in progress.

Currently it is possible to communicate with a smartcard directly connected to a Arduino board or connected via a TDA8024T (or compatible chips. e.g. DS8024).

All tests have been done with a smart card slot connected directly to the Aruino board.

Working:
- Activation of asynchronous and synchronous smart cards
- Exchanging data with supported Smart card (Sending / Receiving)
- Asychron T=0 APDU communication.
- Basic sychron communication
- ETU calculation from TS byte.
- Support class for SLE4432 / SLE4442 / SLE4441 and SLE4440 compatible sychron smartcards.
Mostly used for secure data storage.

Open points:
- Error handling not completly implemented.
No retries if parity error is found.
- Setup of communication parameters from ATR
- T=1 communication not supported (Still possible via "raw" sendBytes(..) / receiveBytes(..))