Merge pull request #1756 from kubernetes-incubator/fix_bool_assert

Fix bool check assert

roles/kubernetes/preinstall/tasks/verify-settings.yml

@@ -30,7 +30,8 @@
 
 - name: "Stop if known booleans are set as strings (Use JSON format on CLI: -e \"{'key': true }\")"
   assert:
-    that: item|type_debug == 'bool'
+    that: hostvars[inventory_hostname][item]|type_debug == 'bool'
+    msg: "{{hostvars[inventory_hostname][item]}} isn't a bool"
   run_once: yes
   with_items:
     - kubeadm_enabled