Initialize variables for theme THEME according to settings in ARGS.
Each of the arguments in ARGS should be a list of this form:
(SYMBOL EXP [NOW [REQUEST [COMMENT]]])
SYMBOL is the variable name, and EXP is an expression which
evaluates to the customized value. EXP will also be stored,
without evaluating it, in SYMBOL's `saved-value' property, so
that it can be restored via the Customize interface. It is also
added to the alist in SYMBOL's `theme-value' property (by
NOW, if present and non-nil, means to install the variable's
value directly now, even if its `defcustom' declaration has not
been executed. This is for internal use only.
REQUEST is a list of features to `require' (which are loaded
prior to evaluating EXP). COMMENT is a comment string about SYMBOL.