Add helper to open iptables with pacemaker/cman.

Install packages on RHEL
TODO: manage service, provider for configuration, ...
Rename Service[apache] to Service[httpd]
Use firewall module instead of the iptables one.
Remove unused parameter
pacemaker::mysql: undef performance default

Will use mysql's default performance value.
Merge pull request #18 from mremy/begin_pacemaker_with_cman

Add helper to open iptables with pacemaker/cman.