Use USART 0 connected to the SIM card side to sniff the communication.
The card side can also measure ETU times.
Do proper pin initialization.
This code can already capture the ATR communication between phone and card.
This way we can easily check with 'diff' for differences in our code and
Atmel softpack. Also, this layout is more suitable for building various
different firmware images (e.g. factory-test, dfu-loader, main
application) for a variety of different boards (simtrace, owhw, qmod).
