2002-05-31  Havoc Pennington  <hp@redhat.com>

	* src/theme.c (multiply_alpha): now just uses
	meta_gradient_add_alpha
	(draw_op_as_pixbuf): implement alpha gradients for tint, gradient,
	and image draw ops, so I can implement garrett's stuff.

	* src/gradient.c (meta_gradient_add_alpha): new function to
	multiply the alpha channel of a pixbuf by an alpha gradient