Backuping up multiple repositories but not the whole account

[McNetic]

I'd like to back up multiple repositories from my account, but not the whole thing, as I have forked various big repositories I just made some small (or no) contributions to. I found no way to to this out of the box, as it is only possible to select a single repository for backup. Calling the program multiple times with different repositories and the same backup directory does not work either, as the last_update state is not tracked per repository, but only once in the backup directory root.

Would you agree on fixing this, either by making it possible to give multiple repositories to backup, or by moving the last_update state into the repository directory in the backup dir (or preferably both)? I'd be willing to provide pull requests for at least a part of the proposed changes.