could not install centos-release-openstack-liberty in the centos7

[wu]

[root@controller ~]# yum search openstack
已加载插件：fastestmirror
Loading mirror speeds from cached hostfile
 * base: mirrors.163.com
 * extras: mirrors.cn99.com
 * updates: mirrors.cn99.com
========================================================= N/S matched: openstack ==========================================================
centos-release-openstack-newton.noarch : OpenStack from the CentOS Cloud SIG repo configs
centos-release-openstack-ocata.noarch : OpenStack from the CentOS Cloud SIG repo configs
centos-release-openstack-pike.x86_64 : OpenStack from the CentOS Cloud SIG repo configs

without the support of centos-release-openstack-liberty from OpenStack repository

-----------------------------------
Release: 0.1 on 2016-11-24 07:54
SHA: cc8b39934de4de69e5235ca8e5c4d4b567d0f418
Source: http://git.openstack.org/cgit/openstack/openstack-manuals/tree/doc/install-guide/source/environment-packages.rst
URL: https://docs.openstack.org/liberty/zh_CN/install-guide-rdo/environment-packages.html

[Andreas Jaeger (jaegerandi)]

Liberty is end-of-life, we cannot help here anymore.

[wu (jiechu)]

Thank you for your response, could you answer my question below ? it means a lot to me.
(1) I have an existing cluster of liberty. how could i add node to it ?
(2) Is there any method could i use to upgrade my liberty cluster to another version ?