Remove temp files created by submit_debug_info

[vcabbage]

Currently submit_debug_info.py doesn't clean up the the temp files it creates. This PR adds a finally statement to remove the temp files created by the create_archive function.

Added a remove_dir function to st2debug/utils/fs.py for consistency with the remove_file function.

[Kami]

Great, thanks.

We also need to make sure directory and file is not removed when using --review option, right?

[vcabbage]

According to the description, --review generates the tarball. This only removes the temp dir, the tarball will still be output.

    parser.add_argument('--review', action='store_true', default=False,
                        help='Generate the tarball, but don\'t encrypt and upload it')

[Kami]

@vcabbage Alright, great - then we should be fine.

On a related note - it would be great if you can add a test case for this change.

[vcabbage]

Difficult to test as written. I could check the number of files int /tmp and verify there are no additional files after create_archive is run, though that sounds a bit flaky. Or I could save the temp dir path to an attribute and check for it's existence directly.

Do you have a preference (or better approach)?

[Kami]

Would need to dig in, but in short, we would probably need to modify some methods to store a list of directories and files which are created...

[vcabbage]

Since it deletes the entire directory I added a test to check if the directory exists after running. Let me know if that works.

[Kami]

Yep, that works - thanks!

[Kami]

Merged, thanks.