Switching Vagrant box to Xenial

Change-Id: If874cace314e0a1a4e9934a8973e197a656c5c86
diff --git a/ansible/group_vars/all b/ansible/group_vars/all
index 6baada9..c93d464 100644
--- a/ansible/group_vars/all
+++ b/ansible/group_vars/all
@@ -4,6 +4,6 @@
 proxy_url2: http://{{ facter_ipaddress_eth1 }}
 registry_url: 10.100.198.220:5000/
 jenkins_ip: 10.100.198.220
-debian_version: trusty
+debian_version: xenial
 docker_cfg: docker.cfg
 docker_cfg_dest: /etc/default/docker