Pull password length from pam_passwordqc

[puck]

Also return passphrase settings if configured. People may want to enforce these settings differently from password settings.

[puck]

I happy to provide a sample PAM config file for pam_passwordqc if that'd be useful.

[puck]

Sample config line:

password        requisite      pam_passwdqc.so min=disabled,disabled,18,18,18 passphrase=6 random=56 enforce=everyone

Minimum password length is 18 characters, passphrase at least 6 words.