fixed: option "-a/--no-update-ini" is not shown in usage
fixed: Cygwin 1.7 is already an upstream

Cygwin 1.5 is a legacy version
fixed: error parsing Cygwin 1.7 setup.ini file

It seems Cygwin 1.7 introduced "message" fields in setup.ini,
but cyg-apt knew nothing about it, so it fails