(Q_vulgar): New variable.

(Q_vulgar): New variable.
(Q_vulgar_of): New variable.
(Fput_char_attribute): Convert char-refs in value of `{->|<-}vulgar'
to characters and put reverse links.
(Fsave_char_attribute_table): Use `Fchar_refs_simplify_char_specs' for
`{->|<-}vulgar'.
(syms_of_chartab): Add new symbols `{->|<-}vulgar'.