2001-11-13  Sven Neumann  <sven@gimp.org>

	* app/base/temp-buf.c: added some safety checks.

	* app/widgets/Makefile.am
	* app/widgets/widgets-types.h
	* app/widgets/gimpimagefilepreview.[ch]: a new class implementing
	special	GimpPreview methods for GimpImagefile.

	* app/core/gimpimagefile.c: added code to load thumbnails according
	to the proposed Thumbnail Managing Standard
	(see http://triq.net/~pearl/thumbnail-spec/). Pretty much untested.

	* app/widgets/gimpcontainerview-utils.c: plugged a memleak.

	* app/widgets/gimpimagepreview.c: simplified.

	* app/widgets/gimppreview.c: tell it about GimpImagefilePreview.