Added the openSUSE package
Created by: Mailaender
Packaged it and submitted https://build.opensuse.org/request/show/416016 for review. As the Gtk3 requirements are quite high, this is currently exclusively available to @openSUSE's rolling release variant Tumbleweed. If you want to get listed with a nice screenshot, we will need to submit this to openSUSE:Factory including appropriate meta data: https://people.freedesktop.org/~hughsient/appdata/