* actions/unarchive: fix unarchive from remote url
Currently unarchive from remote url does not work because the core
unarchive module was updated to support 'remote_src' [1], but the
unarchive action plugin was not updated for this. This causes failures
because the action plugin assumes it needs to copy a file to the
remote server, but in the case of downloading a file from a remote
url a local file does not exist, so an error occurs when the file is
not found.
[1] https://github.com/ansible/ansible-modules-core/commit/467516e
* test_unarchive: fix test with wrong remote_src use
The non-ascii filenames test had improperly set remote_src=yes even
though it was actually copying the file from the local machine (i.e.
the file did not already exist remotely). This test was passing
until the remote_src behavior of unarchive was fixed in 276550f.
When using the "creates" option with the unarchive module, set changed
to False if the file already exists. This behavior is consistent with
other modules which use "creates", such as command and shell.
