* gtk/gtkprinteroption.h:
 * gtk/gtkprinteroptionwidget.c:
 * modules/printbackends/cups/gtkprintbackendcups.c:
   add GTK_PRINTER_OPTION_TYPE_PICKONE_PASSWORD,
   GTK_PRINTER_OPTION_TYPE_PICKONE_PASSCODE,
   GTK_PRINTER_OPTION_TYPE_PICKONE_REAL,
   GTK_PRINTER_OPTION_TYPE_PICKONE_INT,
   and GTK_PRINTER_OPTION_TYPE_PICKONE_STRING options to support a subset
   of the new CUPS 1.2 custom options spec