Introduce OpenStack Heat as additional provisioner

ONAP will mainly be installed on a Kubernetes cluster installed
on Openstack. The creation of the resources (instances, networks, etc.)
are done using Heat so this change prepares the engine for Heat
introduction by adding 2 new parameters:
- provisioner: it can be set by using -r
- uri to heat template: it can be set by using -t

Change-Id: Iedf7848519487a35a2cf5c823e23d6ba72bdb006
diff --git a/playbooks/roles/install-configure-bifrost/tasks/download-image.yml b/playbooks/roles/install-configure-bifrost/tasks/download-image.yml
new file mode 100644
index 0000000..0c1a932
--- /dev/null
+++ b/playbooks/roles/install-configure-bifrost/tasks/download-image.yml
@@ -0,0 +1,43 @@
+---
+# ============LICENSE_START=======================================================
+#  Copyright (C) 2019 The Nordix Foundation. All rights reserved.
+# ================================================================================
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# SPDX-License-Identifier: Apache-2.0
+# ============LICENSE_END=========================================================
+- set_fact:
+    source: "{{ item.source }}"
+    destination: "{{ item.destination }}"
+    download_image: "{{ item.download }}"
+
+- block:
+  - name: Remove existing image {{ destination }}
+    file:
+      path: "{{ destination }}"
+      state: absent
+
+  - name: Get sha256sum of image {{ source }}
+    uri:
+      url: "{{ source }}"
+      method: HEAD
+    register: header
+
+  - name: Download image
+    get_url:
+      url: "{{ source }}"
+      dest: "{{ destination }}"
+      mode: 0644
+      sha256sum: "{{ header.x_checksum_sha256 }}"
+  when: download_image
+  become: yes