[CORD-1935]
Ping ONF website instead of google DNS server as test

Change-Id: If86eacba9e1d988d7c5d9de6c460ca750b3bc905
(cherry picked from commit d7b8ffb0ba08a8fe2766c670d1b305ea46564d42)
diff --git a/roles/head-prep/tasks/main.yml b/roles/head-prep/tasks/main.yml
index e9254b5..afa7be3 100644
--- a/roles/head-prep/tasks/main.yml
+++ b/roles/head-prep/tasks/main.yml
@@ -49,9 +49,11 @@
     - libssl-dev
     - libvirt-bin
     - python-dev
+    - python-dnspython
     - python-glanceclient
     - python-keystoneclient
     - python-lxml
+    - python-netaddr
     - python-neutronclient
     - python-novaclient
     - python-pip