Failure to fetch image stops fetch of rest of images

[dteviot]

(Note for me.)
Sometimes the attempt to get the high resolution version of an image fails. (e.g. WayBackMachine did not preserve the file.)
In this case, the HTTP exception that is thrown aborts the "fetch all images" operation.

Need an option to say "fetch rest of images on image failure". In which case, use the thumbnail image on the original page and try fetching the rest of the images.

[belldandu]

Noticed this too. Depending on the error it should wait a few seconds and try to refetch the image (like when it says service unavailable)

Basically an option like "Attempt to re-fetch images on non 404 errors"
The retry amount could be user specified with a default of 3.

[dteviot]

See also #27, at minimum, need to return more useful error message when there is a network failure.

[dteviot]

I believe this is fixed by #128