(custom-unlispify-remove-prefixes): Reference to

(custom-unlispify-remove-prefixes): Reference to
related variables added.
(custom-variable-default-form): New variable controlling default
display form for customization of variables.
(custom-variable): widget `:form' is nil before initialization.
(custom-variable-value-create): Initialize `:form' to
`custom-variable-default-form'.
(custom-face-default-form): New variable controlling default
display form for customization of faces.
(custom-face): widget `:form' is nil before initialization.
(custom-face-value-create): Initialize `:form' to
`custom-face-default-form'.