title: Pass a file and variables through --extra-vars
body: <p>I see that <a href="http://docs.ansible.com/ansible/playbooks_variables.html#passing-variables-on-the-command-line" rel="noreferrer">files can supply variables to Ansible</a> through the command line using <code>--extra-vars "@some_file.json"</code>, or variables can be set in strings as key=value. Is it possible to do both? And if so, what's the syntax?</p>