Improve playbook to setup gate nodes

* use become instead of sudo
* use file instead of shell to change file modes
* rename setup_nodes.yml to playbook-setup-nodes.yml

Change-Id: I69eda1f034b97d13be76efc91458b6d762c76baf

tools/playbook-setup-nodes.yml

@@ -1,6 +1,7 @@
 ---
 - hosts: all
-  sudo: yes
+  become: true
+
   tasks:
   - name: Setup /etc/hosts
     copy:
@@ -22,14 +23,19 @@
       mode: 0755
 
 - hosts: all
+  become: true
+
   tasks:
   - name: Create log directory for node
     file:
       state: directory
       path: /tmp/{{ inventory_hostname }}
+    become: false
 
   - name: Run node setup
-    shell: sudo /tmp/setup.sh
+    shell: /tmp/setup.sh
 
-  - name: Changing permissions of docker socket to 666
-    shell: sudo chmod 0666 /run/docker.sock
+  - name: Changing permissions of Docker socket to 666
+    file:
+      path: /run/docker.sock
+      mode: 0666

tools/setup_gate.sh

@@ -132,7 +132,7 @@ EOF
 }
 
 function setup_node {
-    ansible-playbook -i ${RAW_INVENTORY} tools/setup_nodes.yml
+    ansible-playbook -i ${RAW_INVENTORY} tools/playbook-setup-nodes.yml
 }
 
 function setup_logging {