ssl: enable makedirs
cpufreq: add service state for cpufreq scanling
nagios: add config & default files
ldap: ubuntu config is /etc/ldap/ldap.conf
fstab: use variable to simplify config
network: add ipv4 address checker
mail: update exim4 config, disable ipv6 for ubuntu
snmpd: add /etc/sysconfig/snmpd for centos
fstab: indent fstab field
redis: add check of srvs
package: named -> bind9 for ubuntu
iptables: add config for CentOS

put all rules in /etc/iptables/
rsyncd: add support for centos
syslogd: add support for centos
crond: add support for centos
centos: add default config
ubuntu: add pkg.installed for vim & gawk
selinux: disable for centos
named: package name is bind for centos
exim: update config for centos