adds ability to purge when images in container are broken

[orangewolf]

we had a bunch of registries with 0 length or otherwise undeleteable tags in them. We hacked around this by pushing a small image to those tags and then re-running the delete.

[glensc]

@orangewolf do you have ideas why it happens? it has happened for me too in the past, when i excessively ran delete from gitlab ui. but i haven't noticed these 0 byte errors for several months. yet i have now cleanup automation in place and run registry-garbage-collect. or perhaps gitlab fixed something?

[n0madic]

I agree with @glensc - you need to check the return value of the delete_image function and make the logic in __main__

[orangewolf]

thank you for the great feedback. I won't have cycles to digest and respond until Friday, but I will pick it back up then.

[lexfrei]

@orangewolf which Friday? :)