gdbus: Fixup d-bus interface naming style
gdbus: Fixup d-bus interface naming style

And conform to usual GNOME naming conventions.

gicmo/gvfs,gicmo/gvfs,xkahn/gvfs-cmis,philipl/gvfs,xkahn/gvfs-cmis,gicmo/gvfs,philipl/gvfs,gicmo/gvfs,halfline/gvfs,halfline/gvfs,halfline/gvfs,philipl/gvfs,xkahn/gvfs-cmis,xkahn/gvfs-cmis