Extract printer setup variables into a struct
Extract printer setup variables into a struct

So that it can be passed as a single parameter to functions as we
extract-function to make cups_request_printer_list_cb more manageable.

Note that not all of the affected variables are changed in this
changeset. Those are in extracted functions and will be addressed in the
next two changes.

johne53/MB3Gtk-2,johne53/MB3Gtk-2,johne53/MB3Gtk-2,Distrotech/gtk,johne53/MB3Gtk-2,johne53/MB3Gtk-2,Distrotech/gtk,Distrotech/gtk,Distrotech/gtk,Distrotech/gtk