Test improvements for xpack + httplib2 support

tasks/elasticsearch-RedHat.yml

@@ -20,3 +20,7 @@
   yum: name={% if es_custom_package_url is defined %}{{ es_custom_package_url }}{% else %}{{ es_package_url }}-{{ es_version }}.noarch.rpm{% endif %} state=present
   when: not es_use_repository
   register: elasticsearch_install_from_package
+
+# ansible uri module requires httplib2
+- name: pip httplib2
+  pip: name=httplib2 extra_args="--user"