add redis play

playbooks/edx-east/redis.yml

+- name: Deploy redis
+  hosts: all
+  become: True
+  gather_facts: True
+  roles:
+    - aws
+    - redis
+    - role: datadog
+      when: COMMON_ENABLE_DATADOG
+    - role: splunkforwarder
+      when: COMMON_ENABLE_SPLUNKFORWARDER
+    - role: newrelic
+      when: COMMON_ENABLE_NEWRELIC
+    - role: newrelic_infrastructure
+      when: COMMON_ENABLE_NEWRELIC_INFRASTRUCTURE