Package gobject-introspection 1.79.1

@smcv gobject-introspection 1.78.1-15 was autosynced to Ubuntu today. Ubuntu has glib 2.79.1. Ubuntu's publishing system won't allow the new gobject-introspection to be published because it tries to build an older version of binary packages that are already in Ubuntu.

I had trouble with dh_girepository when I tried to not build those binary packages so I guess the way forward is to package the new gobject-introspection version (for Experimental and Ubuntu).

Could you review since you did a lot of prep work for this already?