Add gtkprintoperationpreview.[ch] Set default preview command. Hardcoded

Add gtkprintoperationpreview.[ch] Set default preview command. Hardcoded

2006-06-02  Alexander Larsson  <alexl@redhat.com>

	* gtk/Makefile.am:
	Add gtkprintoperationpreview.[ch]
	Set default preview command. Hardcoded for now.

	* gtk/gtkmarshalers.list:
	Add BOOLEAN:OBJECT,OBJECT,OBJECT

	* gtk/gtkprintbackend.c:
	Add preview command property.

	* gtk/gtkprintcontext.[ch]:
	Make less dependent on PrintOperation for output settings
	Externally set cairo_t and dpi. Resettable.
	Create fontmap without metrics hinting (so that print preview
	text layout doesn't depend on zoom level).

	* gtk/gtkprintoperation-private.h:
	* gtk/gtkprintoperation-unix.c:
	* gtk/gtkprintoperation.[ch]:
	Initial work on print preview API and default implementation
	using an external preview app.

	* gtk/gtkprintoperation-win32.c:
	Some needed updates. Not done, needs more work.

	* gtk/gtkprintoperationpreview.[ch]:
	New interface used in print preview api.

	* gtk/gtkprintunixdialog.c:
	Add print preview dialog.

	* tests/print-editor.c:
	Test using an custom print preview widget.