Feature request: a flag for download to fetch all data

[lukebatchelor]

If you ever get in an inconsistent state (i.e from a bug like #15) where you have the latest data, but not data before it, currently there is no way to get the missing data.

A couple of ways to solve this

• We could either refactor how we decide which builds to download (looking at the list
  of files we have currently and starting from the first missing),
• We could add it as a flag (--force, --all) that works the same as currently (downloading backwards), but instead of stopping when we reach one we already know, we continue going back, each time checking if we have the file before doing the request