2008-10-11  Michael Natterer  <mitch@gimp.org>

	* app/gegl/gimpoperationpointcomposer.[ch]: add an empty abstract
	GeglOperationPointComposer subclass which can be used to hook in
	common debug or test or whatever code for below layer modes.

	* app/gegl/gimpoperation*mode.[ch]: add empty stubs of layer mode
	operations which do nothing but copying input to output.

	* app/gegl/Makefile.am
	* app/gegl/gegl-types.h: add them here and reordered things a bit.

	* app/gegl/gimp-gegl.c (gimp_gegl_init): register the new
	operations.

	* app/gegl/gimp-gegl-utils.c (gimp_layer_mode_to_gegl_operation):
	return the new operations.


svn path=/trunk/; revision=27239