drop unused etcd logic

Fixes #1660

roles/etcd/defaults/main.yml

@@ -3,7 +3,6 @@
 etcd_cluster_setup: true
 
 etcd_backup_prefix: "/var/backups"
-etcd_bin_dir: "{{ local_release_dir }}/etcd/etcd-{{ etcd_version }}-linux-amd64/"
 etcd_data_dir: "/var/lib/etcd"
 
 etcd_config_dir: /etc/ssl/etcd

roles/etcd/tasks/install_docker.yml

@@ -1,5 +1,4 @@
 ---
-# Plan A: no docker-py deps
 - name: Install | Copy etcdctl binary from docker container
   command: sh -c "{{ docker_bin_dir }}/docker rm -f etcdctl-binarycopy;
            {{ docker_bin_dir }}/docker create --name etcdctl-binarycopy {{ etcd_image_repo }}:{{ etcd_image_tag }} &&