Add epel role.
Add rpmbuild role.
Add cron role.
Add ntp role.
Add sysstat role.
Add roles to mroonga.yml
Remove epel task from common role.
Remove ntp task from common role.
Remove sysstat task from common role.
Create timezone role.
Create devtools role.
Create xbuild role.
Create git role.
Create self_signed_certificate role.
Use fqdn hostname for self_signed_certificate.
Split tasks in self_signed_certificate role.
Remove devtools and yum-utiles from rpmbuild.
Add monit role.
Add nginx role.
Add iptables role.