2004-09-09  Sven Neumann  <sven@gimp.org>

	* libgimpwidgets/gimppreviewarea.[ch]: allow to set a maximum size
	and center the preview area if its allocation extends the maximum.

	* libgimpwidgets/gimppreview.[ch]: derive from GtkVBox, moved the
	toggle button out of the table and put the table into an aspect
	frame. Added an API to set the preview boundaries. Set the maximum
	size of the GimpPreviewArea from that function.

	* libgimpwidgets/gimpwidgets.def: added new entries.

	* libgimp/gimpdrawablepreview.c: use gimp_preview_set_bounds().

	* plug-ins/common/gauss.c: pack the preview widget so that it
	resizes with the dialog.