Update PAM configurations for RPM-based distros and initial test script

[docsmooth]

Update the Linux hardening guidelines to refer to the correct files on RHEL / SuSE based distros (/etc/pam.d/password-auth-ac). Not including /etc/pam.d/system-auth-ac since that was deprecated in RHEL 5, which is unsupported.

Also, an initial version of a perl test script to automate testing to these guidelines, yet incomplete.

[takeshixx]

Thanks for your submission. The hints for the different operating systems and distros are very useful, I think we should track this in the future and add further hints.

The script is a good idea as well, but I think we should keep this out of the repo until we have something that does all the checks properly. Maybe we should discuss the topics that are not covered by similar tools (like lynis) first to see if it makes sense to implement yet another auditing tool.

I suggest you to resubmit 8e65180 without the script. Feel free to submit the script to a develop branch, maybe that could be a good start to further develop something like a audit script.