Move the project to gitlab.gnome.org
I suggest we move to gitlab.gnome.org, I know a few GNOME devs who complained about having a library now fairly central to GNOME living were the GNOME devs aren't. Other simply would prefer to see it there.
I suggest we move the project to GNOME and we keep developing it there after releasing libhandy 0.0.10. The number of issues and opened MRs here is fairly small, so we could either move them or keep working on them from here in parallel of the new location. New issues should be filed at gitlab.gnome.org.