* libgimp/gserialize.c
	* libgimp/gserialize.h: Changed the enum values to allow for
 	simpler future expansion.

	* libgimp/parasite.c
	* libgimp/parasite.h: s/persistant/persistent/.
 	new accessor functions for parasites.  #defines for new flags.

	* app/paintbrush.c: added timeing code for brush strokes.
  	It is #ifed out, and is only valid for shift clicks.

	* app/parasite_cmds.h: fixed a warning

	* app/parasitelist.h
	* app/parasitelist.c: added _for_each and _length functions

	* app/gimpdrawable.c:  set the dirty flag when adding or removing a
 	persistent parasite

	* app/gimpimage.c: set the dirty flag when adding or removing a
 	persistent parasite.  Fixed bug and removed debug statements in
 	merge_down.

	* app/xcf.c: save and load resolution, parasites, and tattoos.

	* app/main.c: updated the deserialize test.

	* plug-ins/tiff/tiff.c
	* plug-ins/gif/gif.c: use PARASITE_PERSISTENT define instead of 1

	* plug-ins/bmp/bmp.c
	* plug-ins/bmp/bmp.h: declare some struct variable as extern.

	* app/paint_funcs.c: Lots of optimizations aimed at speeding up
 	painting.  Should see a 2-4X speed up on most painting
 	(depending on paint modes, brush size etc.)

	* app/drawable.c: check for NULL drawable in drawable_ID.
  	this stops us from being crashed by ill-behaved plug-ins