WIP: Add a new playbook for stopping cluster

Hopefully without data loss

ansible_playbooks/stop-cluster

@@ -0,0 +1,23 @@
+---
+- name: Stop cluster
+  hosts: consul_instances
+  serial: 1
+
+  tasks:
+    - name: Stop Nomad
+      systemd:
+        name: nomad
+        state: stopped
+      become: true
+
+    - name: Stop Vault
+      systemd:
+        name: vault
+        state: stopped
+      become: true
+      
+    - name: Stop Consul
+      systemd:
+        name: consul
+        state: stopped
+      become: true