Moved the replace function from mitm.py to replace.py.
This implementation is context insensitive for now. It would be
better, to have a mitm class or to pass state information to the
function. Because how else can the MITM code know, whether it gets
passed data to or from the sim card, to or from the phone?
When the command a0 c0 00 00 16 was send, and the the bytes
a0 c0 00 00 where read first, and then only the byte 16 was read
from simtrace, the code never entered the if condition if cmd is not
None, and therefore never executed send_receive_cmd.
Bug fix: Check for state APDU_S_SEND_DATA after apdu_split (parsing)
the ACK-instruction byte, in case it was an instruction which requires
an answer from the SIM card.
* Sniffer uses phone endpoints for communication and the ringbuffer
routines the phone communication uses
* Most times the Usart1 interrupt is not triggered, and therefore
no values are recorded
