- Ability to specify multiple masters
  - configures the CA only a single time on the first master
  - creates and distributes additional certs for additional master hosts

- Depending on the status of openshift_master_cluster_defer_ha (defaults to
  False) one of two actions are taken when multiple masters are defined
  1. If openshift_master_cluster_defer_ha is true
     a. Certs/configs for all masters are deployed
     b. openshift-master service is only started and enabled on the master
     c. HA configuration is expected to be handled by the user manually after
        the completion of the playbook run.
  2. If oepnshift_master_cluster_defer_ha is false or undefined
     a. Certs/configs for all masters are deployed
     b. a Pacemaker/RHEL HA cluster is configured
        i. VIPs are configured based on the values of
           openshift_master_cluster_vip and
           openshift_master_cluster_plublic_vip
        ii. The openshift-master service is configured as an active/passive
            cluster service

- Add support to bin/cluster for specifying etcd hosts
  - defaults to 0, if no etcd hosts are selected, then configures embedded
    etcd
- Updates for the byo inventory file for etcd and master as node by default
- Consolidation of cluster logic more centrally into common playbook
- Added etcd config support to playbooks
- Restructured byo playbooks to leverage the common openshift-cluster playbook
- Added support to common master playbook to generate and apply external etcd
  client certs from the etcd ca
- start of refactor for better handling of master certs in a multi-master
  environment.
  - added the openshift_master_ca and openshift_master_certificates roles to
    manage master certs instead of generating them in the openshift_master
    role
- added etcd host groups to the cluster update playbooks
- aded better handling of host groups when they are either not present or are
  empty.
- Update AWS readme