def add_membership(connection, peer_url)
      info "Adding new etcd membership info with peer URL #{peer_url}"
      connection.post(:body => JSON.generate(peerURLs: [peer_url]),
                      :headers => { 'Content-Type' => 'application/json' })
    end
def add_membership(connection, peer_url)
      info "Adding new etcd membership info with peer URL #{peer_url}"
      connection.post(:body => JSON.generate(peerURLs: [peer_url]),
                      :headers => { 'Content-Type' => 'application/json' })
    end
Add new peer membership

 @param [Excon::Connection] etcd HTTP members API connection
 @param [String] The peer URL of the new peer to be added to the cluster