Merge pull request #3438 from edx/jibsheet/playbook-for-running-security-role

Simple playbook to take security updates on hosts

playbooks/edx-east/apply-security.yml

+# Applies the security role to a set of inventories.  Ensures that security updates
+# are taken on these machines.
+#
+# This is useful if you have a set of deployed instances that are not periodically
+# upgraded via replacement (such as your persistence layers).
+#
+# ansible-playbook -v -i ec2.py, apply-security.yml -limit tag_Name_Snowflake
+# ansible-playbook -v -i hostname, apply-security.yml
+
+- name: Apply security updates
+  hosts: all
+  gather_facts: True
+  become: True
+  vars:
+      SECURITY_UPGRADE_ON_ANSIBLE: true
+  roles:
+      - security