Bug#886063: libgnomecanvas: Don't release with Buster

[Borden Rhodes]

The Xournal package requires this package. If you refer to
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=885777#17, it
appears that this package has been flagged for removal somewhat
over-zealously:

"libgnomecanvas is not related to libgnome in any way despite the
name. It provides a high-performance canvas widget for GTK2, it is the
standard canvas widget for GTK2. There is no good replacement for
GTK3. I am not aware of any serious issues with it apart from it being
old."

I depend on Xournal, and as there is no suitable GTK3 replacement, I'm
curious whether it is possible to appeal the decision to remove
libgnomecanvas on the grounds that it apperntly is not part of the
libgnome code base.