* Add check_mode to get_url that does a HEAD request to make sure the URL exists, but doesn't write the real file
* Add info about new --check behavior to docs. Add tests for the new behavior. Populate res_args with the info the tests are looking for.
* Add trailing comma
* Change nonexistent test URL to http://{{httpbin_host}/DOESNOTEXIST. Fix spacing while I'm at it
* Further spacing cleanup
* State that this functionality is in Ansible 2.4+
* Build HTTPSClientAuthHandler more similarly to how HTTPSHandler works
* Add docs for new client cert authentication
* Support older versions of python
* Simplify logic
* Initial support for client certs in urls.py
* Add an extra test
* Add a get_url test for client cert auth
* Add additional test for client cert auth, with validation and ssl mismatch
* Skip assert when http tester not available
* Update version_added for new options
This change corrects problems reported by the `yamllint` linter.
Since key duplication problems were removed in 4d48711, this commit
mainly fixes trailing spaces and extra empty lines at beginning/end of
files.
