2001-04-23  Michael Natterer  <mitch@gimp.org>

	* app/gimpcontext.[ch]: some minor fixes / cleanup.

	* app/gimpdata.c: forgot to gtk_object_class_add_signals() in
	class_init().

	* app/gui/dialogs-constructors.[ch]: added a tool_tab_func() so
	the notebook tab shows a tool preview, pass a GimpContext to all
	dialog constructors and added set_context() functions for all
	dockable based dialogs so they can be configured to use the
	context of the destination dock when dragging them around.

	* app/widgets/gimpcontainermenuimpl.c: removed debugging output.

	* app/widgets/gimpdialogfactory.[ch]: add a method to create
	dockables (which gets passed the dock the dockable will be added
	to) so the dockables can be created in the right context.

	* app/widgets/gimpdock.[ch]: added a GimpContext attribute, remove
	the dockbooks explicitely in destroy().

	* app/widgets/gimpdockable.[ch]: dockables now know about their
	set_context_func() and can thus be dragged between different
	contexts.

	* app/widgets/gimpdockbook.c: gimp_dockbook_add(): refuse to add
	dockables to dockbooks which are not part of a dock, set the
	dockable's context after adding it.

	* app/widgets/gimpimagedock.[ch]: image docks now keep a pointer
	to the global image list which is passed to them on construction
	so they don't need to know about the global "image_context"
	variable, added an "Auto" button like in L&C.

	* app/gui/dialogs-commands.c: changed accordingly.