Switching Vagrant box to Xenial

Change-Id: If874cace314e0a1a4e9934a8973e197a656c5c86
diff --git a/Vagrantfile b/Vagrantfile
index a9b414a..342262d 100644
--- a/Vagrantfile
+++ b/Vagrantfile
@@ -11,7 +11,7 @@
 
   config.vm.define "voltha" do |d|
     d.ssh.forward_agent = true
-    d.vm.box = "ubuntu/trusty64"
+    d.vm.box = "ubuntu/xenial64"
     d.vm.hostname = "voltha"
     d.vm.network "private_network", ip: "10.100.198.220"
     d.vm.provision :shell, path: "ansible/scripts/bootstrap_ansible.sh"