2005-01-14  Michael Natterer  <mitch@gimp.org>

	* app/core/core-enums.[ch] (enum GimpUndoType): added GIMP_UNDO_INK.

	* app/paint/gimppaintcore.[ch]: added virtual function
	GimpPaintCore::push_undo() and call it.

	* app/paint/gimppaintcore-undo.[ch]: made it the default
	implementation.

	* app/paint/gimpink-blob.[ch]: added blob_duplicate().

	* app/paint/gimpink.[ch]: added a "start_blob" (just like
	GimpPaintCore::start_coords) which gets set whenever we start a
	new stroke or line. Removed ink->lastx and ink->lasty because
	they are the same as paint_core->last_coords.

	* app/paint/Makefile.am
	* app/paint/gimpink-undo.[ch]: new files implementing an
	undo step for ink which restores the last blob used along
	with the whole ink state. Fixes bug #163670.