Refactor ringbuilder

Refactor rinbuilder to map swift::ringbuilder and swift::ringserver

https://github.com/enovance/puppet-openstack-cloud/blob/master/manifests/object/ringbuilder.pp#L31-L49
is the exact same content as swift::ringbuilder

https://github.com/enovance/puppet-openstack-cloud/blob/master/manifests/object/ringbuilder.pp#L51-L69
is the exact same content as swift::ringserver
Merge pull request #477 from enovance/consolidate_ringbuilder

Refactor ringbuilder