Switch to Ansible 2.6

This updates the bifrost playbooks to be compatible with the Ansible
2.6 release.

Change-Id: I352fdccc8ddfce88feb2ea760273bf101eafcd65

playbooks/roles/bifrost-deploy-nodes-dynamic/tasks/main.yml

@@ -78,7 +78,10 @@
     timeout: " {{ wait_timeout | default(1800) }}"
   when: instance_info is defined and instance_info | to_json != '{}'
 - name: "Collect the checksum of the deployment image."
-  stat: path={{deploy_image}}
+  stat:
+    path: "{{ deploy_image }}"
+    get_checksum: yes
+    checksum_algorithm: md5
   register: test_deploy_image
   when: instance_info is not defined or ( instance_info is defined and instance_info | to_json == '{}' )
 - name: "Error if deploy_image is not present, and instance_info is not defined"
@@ -95,7 +98,7 @@
     config_drive: "{{ deploy_url_protocol }}://{{ hostvars[inventory_hostname]['ansible_' + ans_network_interface]['ipv4']['address'] }}:{{ file_url_port }}/configdrive-{{ uuid }}.iso.gz"
     instance_info:
       image_source: "{{ deploy_url_protocol }}://{{ hostvars[inventory_hostname]['ansible_' + ans_network_interface]['ipv4']['address'] }}:{{ file_url_port }}/{{deploy_image_filename}}"
-      image_checksum: "{{ test_deploy_image.stat.md5 }}"
+      image_checksum: "{{ test_deploy_image.stat.checksum }}"
       image_disk_format: "qcow2"
       root_gb: 10
     wait: "{{ wait_for_node_deploy }}"

scripts/env-setup.sh

@@ -5,7 +5,7 @@ set -eu
 # NOTE(pas-ha) the above exports some useful variables like
 # $PYTHON , $PIP and $VENV depending on venv install or not
 
-ANSIBLE_PIP_VERSION=${ANSIBLE_PIP_VERSION:-${ANSIBLE_GIT_BRANCH:-stable-2.4}}
+ANSIBLE_PIP_VERSION=${ANSIBLE_PIP_VERSION:-${ANSIBLE_GIT_BRANCH:-stable-2.6}}
 
 ANSIBLE_PIP_STRING=$(${PYTHON} $(dirname $0)/ansible-pip-str.py ${ANSIBLE_PIP_VERSION})