Incremental backups
As a follow-up to #534, we don't lack much to support incremental backups (mostly CreateBundleFromRefList
in HGitaly understanding the negative refs that gitaly-backup
will send it).
As a follow-up to #534, we don't lack much to support incremental backups (mostly CreateBundleFromRefList
in HGitaly understanding the negative refs that gitaly-backup
will send it).