README.md: Some tweaks
README.md: Some tweaks

resin-io/ostree,gatispaeglis/ostree,sujitfulse/ostree,gatispaeglis/ostree,gatispaeglis/ostree,resin-io/ostree,GNOME/ostree,sujitfulse/ostree,GNOME/ostree,leandrosansilva/ostree,GNOME/ostree,leandrosansilva/ostree,leandrosansilva/ostree,gatispaeglis/ostree,sujitfulse/ostree,gatispaeglis/ostree,leandrosansilva/ostree,sujitfulse/ostree,resin-io/ostree,GNOME/ostree,sujitfulse/ostree,GNOME/ostree,resin-io/ostree,gatispaeglis/ostree,resin-io/ostree,leandrosansilva/ostree