Add update check

[yanokwa]

From https://forum.opendatakit.org/t/xlsform-offline-1-4-0-odk-validation-errors/12544/5

There should there be a way to directly update XLS Form Offline or a check for update? I just had same issue also fixed by updating but I was not aware that XLS Form Offline had been updated

Probably the simplest thing to do here is to to do a quick version check against Github's releases.

[NizamLZ]

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[NizamLZ]

Pull request is under review