FIX: this fixes the "hf mf sniff l d f" command, which has been broken for a while...

FIX: The flushing of logentries.
ADD: "hf mf sniff" - added the sniffing of UID's with a uidlen of 10.

Whats left? The key is not always found even if we use the "mfkey64" approach.

ADD: added the parity_zero attack in "hf mf mifare".  Still not working since piwi's changes to the iso14443a.c,  maybe needs a param to tell it to collect nonces for this special attack.
CHG: extracted some help-texts into usage_* methods. Changed some text as well

FIX:  "hf mf sim" command now uses both  mfkey32 and mfkey32_moebius version to find the key in attack mode.
CHG:  "hf mf sim" also now defaults to emul_memory to read a 4 byte UID.