"Update check failed" and "Offline" at every launch

Fixed for the next release: the automatic update check no longer shows "Update check failed" (checking by hand in Settings still tells you what went wrong), and it doesn't try at all without a connection. "Offline" now means Gratin can't reach its sync server: when your phone says it is offline, Gratin asks the server itself and believes the answer. On a phone, tap the Offline strip to see what it means. If you see "Offline" all the time while other apps are online, check that Gratin is allowed to use Wi-Fi and mobile data in your phone's settings for it. "Contact support" in Settings now includes the connection details, which helps us look into it. Reported by a beta tester.