[bugfix] difok should perform a >= operation against var_password_pam_difok

As noted in https://github.com/OpenSCAP/scap-security-guide/pull/268,
this should be a >= operation for the difok variable
Updating PAM variable var_password_pam_cracklib* --> var_password_pam*

Updating the PAM variable to drop "pam_cracklib" from the name, which
helps its reuse across RHEL7 (where pam_pwquality is used)

[shawnw@ssgdev-rhel7 scap-security-guide]$ grep -rin var_password_pam_cracklib *
OpenStack/input/profiles/stig-rhevm3.xml:241:<refine-value idref="var_password_pam_cracklib_retry" selector="3"/>
OpenStack/input/profiles/stig-rhevm3.xml:243:<refine-value idref="var_password_pam_cracklib_minlen" selector="14"/>
RHEL/6/input/checks/accounts_password_pam_cracklib_minclass.xml:27:  datatype="int" id="var_password_pam_cracklib_minclass" version="1" />
RHEL/6/input/checks/accounts_password_pam_cracklib_minclass.xml:41:    var_ref="var_password_pam_cracklib_minclass" />
RHEL/6/input/fixes/bash/accounts_password_pam_cracklib_maxrepeat.sh:2:populate var_password_pam_cracklib_maxrepeat
RHEL/6/input/fixes/bash/accounts_password_pam_cracklib_maxrepeat.sh:5:	sed -i --follow-symlink "s/\(maxrepeat *= *\).*/\1$var_password_pam_cracklib_maxrepeat/" /etc/pam.d/system-auth
RHEL/6/input/fixes/bash/accounts_password_pam_cracklib_maxrepeat.sh:7:	sed -i --follow-symlink "/pam_cracklib.so/ s/$/ maxrepeat=$var_password_pam_cracklib_maxrepeat/" /etc/pam.d/system-auth
RHEL/6/input/fixes/bash/accounts_password_pam_cracklib_minclass.sh:2:populate var_password_pam_cracklib_minclass
RHEL/6/input/fixes/bash/accounts_password_pam_cracklib_minclass.sh:6:    sed --follow-symlinks -i "/pam_cracklib.so/s/minclass=[0-$var_password_pam_cracklib_minclass]/minclass=$var_password_pam_cracklib_minclass/" /etc/pam.d/system-auth
RHEL/6/input/fixes/bash/accounts_password_pam_cracklib_minclass.sh:8:    sed --follow-symlinks -i "/pam_cracklib.so/s/pam_cracklib.so /pam_cracklib.so minclass=$var_password_pam_cracklib_minclass /" /etc/pam.d/system-auth
RHEL/6/input/profiles/common.xml:242:<refine-value idref="var_password_pam_cracklib_minlen" selector="14"/>
RHEL/6/input/system/accounts/pam.xml:128:<Value id="var_password_pam_cracklib_maxrepeat" type="number" operator="equals" interactive="0">
RHEL/6/input/system/accounts/pam.xml:137:<Value id="var_password_pam_cracklib_minlen" type="number" operator="equals" interactive="0">
RHEL/6/input/system/accounts/pam.xml:200:<Value id="var_password_pam_cracklib_minclass" type="number" operator="equals" interactive="0">
RHEL/6/input/system/accounts/pam.xml:273:which contain more than that number of consecutive characters. Add <tt>maxrepeat=<sub idref="var_password_pam_cracklib_maxrepeat" /></tt>
RHEL/6/input/system/accounts/pam.xml:274:after pam_cracklib.so to prevent a run of (<sub idref="var_password_pam_cracklib_maxrepeat" /> + 1) or more identical characters.
RHEL/6/input/system/accounts/pam.xml:285:<oval id="accounts_password_pam_cracklib_maxrepeat" value="var_password_pam_cracklib_maxrepeat" />
RHEL/6/input/system/accounts/pam.xml:428:Add <tt>minclass=<i><sub idref="var_password_pam_cracklib_minclass" /></i></tt> after pam_cracklib.so entry into the
RHEL/6/input/system/accounts/pam.xml:429:<tt>/etc/pam.d/system-auth</tt> file in order to require <sub idref="var_password_pam_cracklib_minclass" />  differing categories of
RHEL/6/input/system/accounts/pam.xml:446:<oval id="accounts_password_pam_cracklib_minclass" value="var_password_pam_cracklib_minclass"/>
RHEL/7/input/system/accounts/pam.xml:128:<Value id="var_password_pam_cracklib_maxrepeat" type="number" operator="equals" interactive="0">
RHEL/7/input/system/accounts/pam.xml:137:<Value id="var_password_pam_cracklib_minlen" type="number" operator="equals" interactive="0">
RHEL/7/input/system/accounts/pam.xml:200:<Value id="var_password_pam_cracklib_minclass" type="number" operator="equals" interactive="0">
RHEL/7/input/system/accounts/pam.xml:446:<oval id="accounts_password_pam_cracklib_minclass" value="var_password_pam_cracklib_minclass"/>
RHEVM3/input/profiles/stig-rhevm3.xml:241:<refine-value idref="var_password_pam_cracklib_retry" selector="3"/>
RHEVM3/input/profiles/stig-rhevm3.xml:243:<refine-value idref="var_password_pam_cracklib_minlen" selector="14"/>
shared/oval/accounts_password_pam_cracklib_maxrepeat.xml:30:    <ind:subexpression datatype="int" operation="less than or equal" var_ref="var_password_pam_cracklib_maxrepeat" />
shared/oval/accounts_password_pam_cracklib_maxrepeat.xml:33:  <external_variable comment="External variable for pam_cracklib maxrepeat" datatype="int" id="var_password_pam_cracklib_maxrepeat" version="1" />
[shawnw@ssgdev-rhel7 scap-security-guide]$ sed -i 's/var_password_pam_cracklib/var_password_pam/g' OpenStack/input/profiles/stig-rhevm3.xml RHEL/6/input/checks/accounts_password_pam_cracklib_minclass.xml RHEL/6/input/fixes/bash/accounts_password_pam_cracklib_maxrepeat.sh RHEL/6/input/profiles/common.xml RHEL/6/input/system/accounts/pam.xml RHEL/7/input/system/accounts/pam.xml RHEVM3/input/profiles/stig-rhevm3.xml shared/oval/accounts_password_pam_cracklib_maxrepeat.xml
[shawnw@ssgdev-rhel7 scap-security-guide]$ grep -rin var_password_pam_cracklib *
RHEL/6/input/fixes/bash/accounts_password_pam_cracklib_minclass.sh:2:populate var_password_pam_cracklib_minclass
RHEL/6/input/fixes/bash/accounts_password_pam_cracklib_minclass.sh:6:    sed --follow-symlinks -i "/pam_cracklib.so/s/minclass=[0-$var_password_pam_cracklib_minclass]/minclass=$var_password_pam_cracklib_minclass/" /etc/pam.d/system-auth
RHEL/6/input/fixes/bash/accounts_password_pam_cracklib_minclass.sh:8:    sed --follow-symlinks -i "/pam_cracklib.so/s/pam_cracklib.so /pam_cracklib.so minclass=$var_password_pam_cracklib_minclass /" /etc/pam.d/system-auth
[shawnw@ssgdev-rhel7 scap-security-guide]$ sed -i 's/var_password_pam_cracklib/var_password_pam/g' RHEL/6/input/fixes/bash/accounts_password_pam_cracklib_minclass.sh
[shawnw@ssgdev-rhel7 scap-security-guide]$ grep -rin var_password_pam_cracklib *
Update XCCDF to reflect pam_cracklib --> pam_pwquality

Replaced instances of pam_cracklib in XCCDF rules within
RHEL7 rht-ccp profile.
RHEL7 remediation for accounts_password_pam_retry
rhel7 new remediation for accounts_password_pam_dcredit
rhel7 remediation for accounts_password_pam_ucredit
rhel7 remediation for accounts_password_pam_ocredit
rhel7 remediation for accounts_password_pam_lcredit
rhel7 remediation for accounts_password_pam_difok
rhe6/rhel7 remediation for accounts_passwords_pam_faillock_deny
rhel7/rhel6 remediation for accounts_password_pam_unix_remember.sh
rhel6/rhel7 remediation for set_password_hashing_algorithm_systemauth
update set_password_hashing_algorithm_systemauth.sh -- regex bugfix

prior regex did not match appropriately
updated bash remediation for accounts_passwords_pam_faillock_deny.sh

The regex was a bit fubar, needed to extra capture group
Merge pull request #273 from shawndwells/rhel7-pam-pwquality

Misc fixes for RHEL7 PAM, plus bash remediations