Download stuck at 0% working

See https://about.gitlab.com/2016/03/14/gitlab-in-case-you-missed-it/#comment-2570822168

1. This is maybe because our Omnibus package is one giant file?
2. Can we maybe split it up? Or make sure some smaller files are downloaded first?
3. Or advise people how to view something is downloaded at all?
4. Or just warn about this on the download page?

/cc @jacobvosmaer @marin