- Add Daijiten numbers.

- Add Daijiten numbers.
- Use `<-denotational@usage' instead of `<-denotational' for BUCS
  (super abstract) character objects.
(U+5C3A-itaiji-002): New character.
(U+5C65-itaiji-002): New character.
(A-U+5C65-itaiji-003): New abstract node.
(U+5C65-itaiji-003): New character; use `<-denotational' for
U+5C65-itaiji-003.
(U+5C5C): Add `ideographic-structure'; add `sound@ja/on/{kan|go}'; add
some relations for other characters; add representative nodes.
(U-00021C95): Apply new conventions for glyph granularity.
(U+5C5F): Likewise.
(A-MJ057371): Unify U-0002D56D.