* fix incorrect parentheses
* if there was no password on the command line or in .cnf file,
pkt will be "", and we need to request the user to enter the password
Revert the side effect of 7c40996cc8.
Do not convert password hash to its binary representation when a user
entry is loaded. Do it lazily on the first authenticatation attempt.
As a collateral - force all authentication plugins to follow the
protocol and read_packet at least once before accessing info->username
(username is not available before first client handshake packet is read).
Fix PAM and GSSAPI plugins to behave.
New version of PAM plugin (v2.0) added along with the old v1.0.
There the pam module is isolated in the auth_pam_tool application so
cannot crash the server.