[Feature] Auto-Refresh Once Daily

[khatharr]

So there's an option in the settings to automatically refresh the repos on startup, which is a good idea, but I've found that when I'm messing with mods a lot I tend to restart CKAN four or five times, and the automatic check becomes annoying.

I was thinking that there could be an additional auto-refresh option that would only trigger if the modification date on the registry is more than 24 hours ago.