Replace empty usernames with placeholder.

This release addresses issue #3 by adding a placeholder username when importing an empty username with non-empty password. My guess is that Microsoft's credential storage doesn't like empty user names, so it fails to import them, so that's the workaround.

Don't fail completely if one of the accounts fails.

This release fixes the app failing completely if there was an error importing one account. It also outputs info about an account that was failed for the user to check if it is relevant.

Initial release

1.0