Add --ignore to ignore user

[jrwren]

No description provided.

[jrwren]

for #513

[Serene-Arc]

Hi, few things:

• The option you added to the documentation is --ignore, not --ignore-user
• The if statement shouldn't be in the cloner, it should be in the downloader class. The cloner simply inherits from both of them
• If you could write tests for the relevant sets of integrations (the cloner, downloader, and archiver) that would be great. The BDFR needs to have every change tested

[Serene-Arc]

Hey, thanks for fixing the documentation. This test doesn't pass, in fact it doesn't run at all. I more meant integration tests, although it's not bad to have this one as well.