Bug#1127449: Please add support for arithmetic-encoded JPEGs to loupe

[Jeremy Bícha]

I see now that this was requested upstream and the upstream maintainer
is not interested in working on it themselves currently:
https://github.com/etemesi254/zune-image/issues/274

A workaround is to use gimp which still can display the file even
after gdk-pixbuf is switched to glycin.

Thank you,
Jeremy Bícha