Merge pull request #2051 from edx/feanil/update_elasticsearch_playbook

Be able to run this playbook on other clusters.

playbooks/edx-east/elasticsearch.yml

-- hosts: tag_play_commoncluster:&tag_environment_stage:&tag_deployment_edx
+- hosts: all
   sudo: True
-  vars_files:
-    - "{{ secure_dir }}/vars/common/common.yml"
-    - "{{ secure_dir }}/vars/stage/stage-edx.yml"
   vars:
     # By default take instances in and out of the elb(s) they
     # are attached to