Changed default box image to custom centos 7 image
Updated ceph pre-provisioning for centos 7
Facilitated pre-installation of rdo repo for centos 7 to avoid conflict with puppetlabs repo package
Fixed installation of puppet and facter on CentOS7, added comments in script
Fixed installation of puppet and facter for CentOS 7
Added epel class as this is an undocumented req for puppet-openstack  ck 4.2.0
Small fixes to vagrant provisioning
Always install epel repo
Added new undocumented dependency openstacklib