Add conditionals for DD, splunk and new relic.

playbooks/edx-east/jenkins_admin.yml

@@ -3,10 +3,19 @@
   hosts: all
   sudo: True
   gather_facts: True
+  vars:
+    ENABLE_DATADOG: False
+    ENABLE_SPLUNKFORWARDER: False
+    ENABLE_NEWRELIC: False
   roles:
-  - aws
-  - edx_ansible
-  - user
-  - jenkins_admin
-  - hotg
-  - newrelic
+    - aws
+    - edx_ansible
+    - user
+    - jenkins_admin
+    - hotg
+    - role: datadog
+      when: ENABLE_DATADOG
+    - role: splunkforwarder
+      when: ENABLE_SPLUNKFORWARDER
+    - role: newrelic
+      when: ENABLE_NEWRELIC