Initialize faces according to user preferences.
This associates the settings with the `user' theme.
The arguments should be a list where each entry has the form:
(FACE SPEC [NOW [COMMENT]])
SPEC is stored as the saved value for FACE, as well as the value for the
`user' theme. The `user' theme is one of the default themes known to Emacs.
See `custom-known-themes' for more information on the known themes.
See `custom-theme-set-faces' for more information on the interplay
between themes and faces.
See `defface' for the format of SPEC.
If NOW is present and non-nil, FACE is created now, according to SPEC. COMMENT is a string comment about FACE.