(facemenu-read-color, facemenu-colors): New fn, var.

(facemenu-read-color, facemenu-colors): New fn, var.
(facemenu-set-face, facemenu-set-face-from-menu,
facemenu-after-change):	Face property can take a list value; add
to it rather than completely replacing the property.
(facemenu-add-face, facemenu-discard-redundant-faces): New functions.

(facemenu-set-foreground, facemenu-set-background)
(facemenu-get-face, facemenu-foreground, facemenu-background): New
functions and variables.  Faces with names of the form fg:color
and bg:color are now treated specially.
(facemenu-update): Updated for above.