(x-decompose-font-name): While seting each field of

(x-decompose-font-name): While seting each field of
XLFD, set "*" instead of nil to a field which is omitted in the
original font name.
(generate-fontset-menu): Delete code for handling alias (or
nickname). It is now handled in fontset-plain-name.
(fontset-plain-name): Handle alias of fontset name, show more
user-friendy names.
(create-fontset-from-fontset-spec): Add an optional arg STYLE to
create bold, italic, and bold-italic variants of a fonset.