Merge pull request #1654 from edx/feanil/more_facts

Gather facts in edx_ansible play.

playbooks/edx-east/edx_ansible.yml

 - name: Deploy the edx_ansible role
   hosts: all
   sudo: True
-  gather_facts: False
+  gather_facts: True
   vars:
     serial_count: 1
   serial: "{{ serial_count }}"