move xsce_env.py.j2 to prep.yml

roles/1-prep/tasks/prep.yml

@@ -40,6 +40,10 @@
             group=root
             mode=0644
 
+- name: put a python interface to xsce.env
+  template: src=xsce_env.py
+            dest=/etc/xsce/xsce_env.py
+
 - name: create ansible.d facts directory
   file: path=/etc/ansible/facts.d
         owner=root