Fix break with download template in LXC 4.0.12

LXC 0.4.12 removes "--no-validate" from lxc-download template. So old
versions should use this flag but not 4.0.12+

Closes: #3

create_inventory_lxc.yml

@@ -66,13 +66,20 @@
       when: inventory_hostname in groups.lxc_hosts
 
 
+    - name: Check for no-validate parameter in download template
+      shell: "/usr/share/lxc/templates/lxc-download --help | grep no-validate || true"
+      changed_when: false
+      register: lxc_download_validate
+      delegate_to: "{{ ansible_host|default('localhost') }}"
+
+
     - name: Create LXContainer
       lxc_container:
         name: "{{ inventory_hostname }}"
         state: started
         template: download
-        template_options: "-a amd64 -d {{ os_d }} -r {{ os_r }} --no-validate"
-        config: /etc/lxc/ansible.conf
+        template_options: "-a amd64 -d {{ os_d }} -r {{ os_r }} {% if 'no-validate' in lxc_download_validate.stdout %}--no-validate{% endif %}"
+        config: "{{ lxc_config_file|default('/etc/lxc/ansible.conf') }}"
       register: lxc_created
       delegate_to: "{{ ansible_host|default('localhost') }}"