[Enhancement] add PROD variable to RHEL makefiles

- Added $(PROD) to RHEL 6 & 7 Makefiles to match Fedora Makefile as well as make it easier to template
[Enhancement] add PROD variable to Openstack and RHEVM3 Makefiles
o[Enhancement] shared directory python scripts for templatates in Makefiles

- Update Makefiles
- Remove python scripts from content template directories and move to shared
- Fixes #244
Merge pull request #284 from redhatrises/makefile_updates

Makefile updates - add $(PROD) variable
Merge pull request #288 from redhatrises/makefile_shared_updates

[Enhancement] shared directory python scripts for templatates in Makefiles
[RHEL/7, Fedora] Specify exact profile names when generating guides
[RHEL/6] Fix OOM killer termination of oscap probe_file process due to excessive
         memory use. See e.g: https://www.redhat.com/archives/open-scap-list/2014-May/msg00005.html
         or https://github.com/OpenSCAP/scap-security-guide/commit/2eeeca75499f69adeb74f63e9f667c2460ae2435
Merge pull request #297 from iankko/rhel6_fix_oscap_file_probe_oom_killer_termination

[bugfix] [RHEL/6] Fix OOM killer termination of oscap probe_file process due to excessive memory use when evaluating file_permissions_ungroupowned rule
Merge pull request #296 from iankko/v2_rhel7_fedora_specify_profile_names_for_guides

[bugfix] [RHEL/7, Fedora] Specify exact profile names when generating guides -- version #2
[RHEL/6] Use full path to sysctl executable for sysctl remediation scripts
         to prevent errors on RHEL-6 Server when attempting remediation
Merge pull request #298 from iankko/use_full_path_for_rhel6_sysctl_remediation_fixes

[bugfix] [RHEL/6] Use full path to sysctl executable for sysctl remediation scripts to prevent errors on RHEL-6 Server when attempting remediation
[RHEL/7][Fedora] Update IPv6 Kernel Module to sysctl setting

- Migrate IPv6 kernel module disable to sysctl settings
- Enabled for Fedora
- Fixes #60
[RHEL/7] add Sysctl IPv6 Kernel check
[Enhancement] Add initial list of Contributors
Merge pull request #301 from redhatrises/contributors

[Enhancement] Add initial list of Contributors
[RHEL/6, RHEL/7] Fix XCCDF description of (the three per each product) pam_faillock
                 rules so they would be based on the complete second example from the
                 pam_faillock manual page (fixes #302 issue)
[shared] Fix remediation script for 'Set Deny For Failed Password Attempts' issue wrt to
         problems noted in issue #304.
Merge pull request #303 from iankko/rhel6_rhel7_pam_faillock_drop_authsucc_add_preauth_calls

[RHEL/6, RHEL/7] Fix pam_faillock rules recommendations so they wouldn't be thrown out of context
[shared] Fix indentation for accounts_passwords_pam_faillock_deny remediation script yet
         (so it would align with other rows in /etc/pam.d/{password,system}-auth files)
Merge pull request #305 from iankko/shared_fix_accounts_passwords_pam_faillock_deny_remediation

[bugfix] [shared] Fix remediation script for 'Set Deny For Failed Password Attempts wrt to issue #304