2001-01-28  Michael Natterer  <mitch@gimp.org>

	* app/Makefile.am
	* app/gimplayermask.[ch]: new files cut out of layer.[ch]. Renamed
	all functions to gimp_layes_mask_*(). removed artefacts like
	the ref/unref functions.

	* app/apptypes.h: removed the "LayerMask" typedef.

	* app/layer.[ch]: removed the layer mask stuff and renamed all
	functions to gimp_layer_*(). Added temporary typedefs for the old
	function names. The layer mask preview stuff is still there (should
	probably go to new layer_preview.{ch] files).

	* app/gimpimage.[ch]: added
	gimp_image_invalidate_[layer|channel]_previews() formerly known as
	[layer|channel]_invalidate_previews().

	* app/channel.[ch]: moved channel_layer_alpha() and
	channel_layer_mask() here because they are methods of the Channel.

	* app/channel_ops.c
	* app/convert.c
	* app/disp_callbacks.c
	* app/fileops.c
	* app/floating_sel.c
	* app/gimage.c
	* app/gimage_mask.c
	* app/gimpdnd.c
	* app/global_edit.c
	* app/layers_dialog.c
	* app/preferences_dialog.c
	* app/toolbox.c
	* app/undo.c
	* app/xcf.c
	* app/pdb/drawable_cmds.c
	* app/pdb/image_cmds.c
	* app/pdb/layer_cmds.c
	* app/tools/crop.c
	* app/tools/text_tool.c
	* app/tools/transform_core.c
	* tools/pdbgen/pdb.pl
	* tools/pdbgen/pdb/drawable.pdb: changed accordingly, cleanup.