Add VM creation support on Debian jessie

Debian jessie changed the libvirt service name from the prior
release and as such we need additional logic to load the defaults
and a defaults file that represents jessie.

Additionally, we need to ensure that we start the default network
as it may not be started by default on Debian jessie.

Change-Id: I48a64f61d8ba42f76c2df3b984d3090b68e3cf93
Partial-Bug: 1522552

playbooks/roles/bifrost-create-vm-nodes/defaults/dummy-defaults.yml

@@ -0,0 +1,2 @@
+---
+# Note(TheJulia): This file is intentionally left empty. Do not edit.

playbooks/roles/bifrost-create-vm-nodes/defaults/required_defaults_Debian_jessie.yml

@@ -0,0 +1,2 @@
+---
+libvirt_service_name: libvirtd

playbooks/roles/bifrost-create-vm-nodes/tasks/main.yml

@@ -23,6 +23,11 @@
   with_first_found:
     - "../defaults/required_defaults_{{ ansible_distribution }}.yml"
     - "../defaults/required_defaults_{{ ansible_os_family }}.yml"
+- name: "Include OS version-specific defaults"
+  include_vars: "{{ item }}"
+  with_first_found:
+    - "../defaults/required_defaults_{{ ansible_distribution }}_{{ ansible_distribution_release }}.yml"
+    - "../defaults/dummy-defaults.yml"
 # NOTE(cinerama): On Fedora 22, ansible 1.9, ansible_pkg_mgr
 # defaults to yum, which may not be installed. This can be safely
 # removed when we start using an ansible release which prefers dnf.
@@ -39,6 +44,13 @@
   with_items: required_packages
 - name: "Restart libvirt service"
   service: name="{{libvirt_service_name}}" state=restarted
+- name: "Verify default network is running"
+  shell: virsh net-info default |grep Active|grep -q yes
+  register: virsh_network_status
+  ignore_errors: yes
+- name: "Start default network if not running"
+  command: virsh net-start default
+  when: virsh_network_status.rc != 0
 - name: "Create virtual machines"
   script: create_vm_nodes-for-role.sh
   environment: