added cassandra shutdown configuration

requirements.yml

diff --git a/requirements.yml b/requirements.yml
index 9ca1782..b7fa047 100644
--- a/requirements.yml
+++ b/requirements.yml
@@ -5,6 +5,8 @@
 
 - src: https://github.com/carlosfrias/apigee-opdk-stop-components.git
 
+- src: https://github.com/carlosfrias/apigee-opdk-cassandra-shutdown-preparation.git
+
 - src: https://github.com/carlosfrias/apigee-opdk-start-components.git
 
 - src: https://github.com/carlosfrias/apigee-opdk-setup-status.git

rolling-restart.yml

diff --git a/rolling-restart.yml b/rolling-restart.yml
index 47792c6..31ca4d0 100644
--- a/rolling-restart.yml
+++ b/rolling-restart.yml
@@ -1,6 +1,16 @@
 ---
 - name: Perform rolling restart of edge components
-  hosts: ds,rmp,ms
+  hosts: ds
+  gather_facts: no
+  serial: 1
+  roles:
+  - { role: apigee-opdk-cassandra-shutdown-preparation, tags: ['stop', 'restart'] }
+  - { role: apigee-opdk-stop-components, tags: ['pre_restart', 'pre_stop', 'stop'] }
+  - { role: apigee-opdk-start-components, tags: ['pre_restart', 'pre_start','start'], component_start_delay: '{{ start_delay | default(0) }}' }
+  - { role: apigee-opdk-setup-status, tags: ['pre_restart', 'pre_start','start'] }
+
+- name: Perform rolling restart of edge components
+  hosts: rmp,ms
   gather_facts: no
   serial: 1
   roles: