Cache and refreshing

Visitors only ever read the file cache; nothing is fetched on a page view.

• Refresh Now fetches every ticked and configured source and rewrites the cache.
• Clear Cache empties it (the widget shows a placeholder until the next refresh).
• Cache duration - 1 hour, 6 hours, 12 hours (default), 24 hours or 7 days; after that the dashboard marks the cache Stale.
• Only one refresh runs at a time, so a double click can't hammer an API quota.

Scheduled (automatic) refresh is not part of 1.1.0. Click Refresh Now after changing credentials, and whenever you want fresh reviews.