Update selective file sources example

examples/playbooks/selective_file_sources.yml

@@ -13,13 +13,13 @@
     first_available_file:
 
        # first see if we have a file for this specific host
-       - /srv/whatever/${ansible_hostname}.conf
+       - /srv/whatever/{{ansible_hostname}}.conf
 
        # next try to load something like CentOS6.2.conf
-       - /srv/whatever/${ansible_distribution}${ansible_distribution_version}.conf
+       - /srv/whatever/{{ansible_distribution}}{{ansible_distribution_version}}.conf
 
        # next see if there's a CentOS.conf
-       - /srv/whatever/${ansible_distribution}.conf
+       - /srv/whatever/{{ansible_distribution}}.conf
 
        # finally give up and just use something generic
        - /srv/whatever/default