2004-05-03  Michael Natterer  <mitch@gimp.org>

	* app/actions/actions.[ch]: added some utility functions to get a
	Gimp, GimpImage, GimpDisplay and GtkWidget from the "data" pointer
	passed to action callbacks.

	* app/actions/channels-actions.c
	* app/actions/channels-commands.c
	* app/actions/drawable-actions.c
	* app/actions/drawable-commands.c
	* app/actions/edit-actions.c
	* app/actions/edit-commands.c
	* app/actions/file-actions.c
	* app/actions/file-commands.c
	* app/actions/help-commands.c
	* app/actions/image-actions.c
	* app/actions/image-commands.c
	* app/actions/layers-actions.c
	* app/actions/layers-commands.c
	* app/actions/plug-in-actions.c
	* app/actions/plug-in-commands.c
	* app/actions/qmask-actions.c
	* app/actions/qmask-commands.c
	* app/actions/select-actions.c
	* app/actions/select-commands.c
	* app/actions/tools-commands.c
	* app/actions/vectors-actions.c
	* app/actions/vectors-commands.c
	* app/actions/view-commands.c: use the new functions instead of
	duplicating insane macros and if() constructs over and over again.