This commit fixes various bugs that I've noticed on some windows systems with
smartcards that contains multiple certificates:
* With some drivers if you retrieve the ATR while enumerating the NCrypt keys, it seems to
confuse the NCrypt key context (and you're unable to retrieve certificate property). As
we don't use the ATR, let's remove the ATR retrieval.
* if don't give any user or domain on the command line, in settings you get User=Domain=NULL,
but if you pass /u:user, you get User="user" and Domain = ""(empty string not NULL). The
smartcard filtering by user/domain was not ready for that.
57d2a27980