[RHEL/6] Delete unused file_permissions_boot_grub_grub_conf.xml OVAL
         check (file_permissions_grub_conf.xml is used instead)

[RHEL/6] file_permissions_grub_conf.xml:
         * replace path+filename with filepath
         * equip with test_attestation
[RHEL/6, RHEL/7, shared] Start using package_talk-server_removed.xml OVAL check by adding appropriate XCCDF entry
[RHEL/6, RHEL/7] input/services/obsolete.xml - Update title for "talk" group to be more appropriate
[RHEL/6, RHEL/7, shared] Implement OVAL check & XCCDF definition for package_talk_removed rule
[shared/references] Take CCE-27115-5 identifier for accounts_password_pam_cracklib_minclass
rule based on suggestion in: https://lists.fedorahosted.org/pipermail/scap-security-guide/2014-June/005741.html
[RHEL/6] Fix implementation of accounts_password_pam_cracklib_minclass OVAL
check. Provide corresponding XCCDF definition & start using the rule.
[RHEL/6] accounts_password_pam_cracklib_minclass OVAL check:
* update CCE entry with the allocated one
* fix two text entries to be more appropriate as suggested in:
  https://lists.fedorahosted.org/pipermail/scap-security-guide/2014-June/005741.html