calculating of etc/hosts file was broken in ansible2 due to changes in the way hostvars work. Fixed

roles/calculateEtcHosts/tasks/main.yml

+---
 - name: get_groups_json
   template: dest=/tmp/groups src=groups.j2
 
@@ -11,6 +12,5 @@
 - name: write hosts file
   template: dest=/tmp/etcHosts src=etcHosts.j2
 
-
 - name: fetch hosts file
   fetch: src=/tmp/etcHosts dest=files/etcHosts flat=yes

roles/calculateEtcHosts/templates/groups.j2

 { 
   "groups": {{ groups | to_nice_json }},
-  "hostvars": {{ hostvars | to_nice_json }}
+  "hostvars": {
+{% for host in groups['all'] %}
+"{{ host }}" : {{ hostvars[host]|to_nice_json }}
+{% if not loop.last %}
+    ,
+{% endif %}
+{% endfor %}
+}
 }