iteritems not working for dict in py3

[licode]

There is some error if I am using ansible with py3

TASK [kafka : Render and write out kafka configuration files] ***********************
task path: /Users/lili/Research/Dev/playbooks/roles/kafka/tasks/kafka-cfg.yml:38
failed: [bcart01] (item=server.properties) => {
    "changed": false,
    "item": "server.properties",
    "msg": "AnsibleUndefinedVariable: 'dict object' has no attribute 'iteritems'"
}

This fix should work for both py2 and py3.

[licode]

@jtaylor , any comment on this PR?

[jaytaylor]

If you squash and cleanup the commits, I'll gladly merge this!