Add dnf support

This patch adds dnf support for CentOS.

Implements: blueprint centos-and-dnf
Change-Id: I1e83872b86234fb6bf5c0459cbb5d618573f1e24

tasks/neutron_install.yml

@@ -110,7 +110,7 @@
     path:  "{{ neutron_bin | dirname }}/bin/python2.7"
     state: "absent"
   when:
-    - ansible_pkg_mgr in ['yum', 'zypper']
+    - ansible_pkg_mgr in ['yum', 'dnf', 'zypper']
     - neutron_get_venv | changed
 
 - name: Update virtualenv path

tasks/neutron_post_install.yml

@@ -129,7 +129,7 @@
   when:
     - neutron_metadata_checksum_fix | bool
     - neutron_services['neutron-linuxbridge-agent']['group'] in group_names
-    - ansible_pkg_mgr == 'yum'
+    - ansible_pkg_mgr in ['yum', 'dnf']
 
 - name: Ensure the postup/postdown scripts are loaded (SUSE)
   lineinfile:

tests/test-install-previous-neutron.yml

@@ -36,7 +36,7 @@
     - name: Set mount path for kernel modules (CentOS)
       set_fact:
         kernel_module_path: "usr/lib/modules"
-      when: ansible_pkg_mgr == 'yum'
+      when: ansible_pkg_mgr in ['yum', 'dnf']
 
     - name: Neutron extra lxc config
       lxc_container:
@@ -81,7 +81,7 @@
         - libffi-devel
       when:
         - inventory_hostname in groups['neutron_all']
-        - ansible_pkg_mgr == 'yum'
+        - ansible_pkg_mgr in ['yum', 'dnf']
     - include: common/ensure-rabbitmq.yml
       vhost_name: "{{ neutron_rabbitmq_vhost }}"
       user_name: "{{ neutron_rabbitmq_userid }}"