(U+5435): Add `<-denotational@usage' for BUCS+5435; apply new

(U+5435): Add `<-denotational@usage' for BUCS+5435; apply new
conventions for glyph granularity.
(U+5440): Add `<-denotational@usage' for BUCS+5440; add
`sound@ja/on/{kan|go}' and `sound@ja/on/conventional'; unify
DJT-01221.
(U+5443): Add `<-denotational@usage' for BUCS+5443; apply new
conventions for glyph granularity.
(U+545D): Add `<-denotational@usage' for A2-DJT-01232; add
`sound@ja/on/{kan|go}'.
(CU+545D): Unify DJT-01232; add some relations for other characters.
(U+54AC): Add `<-denotational@usage' for BUCS+54AC; add
`sound@ja/on/{kan|go}' and `sound@ja/on/conventional'.
(UU+54AC): Unify DJT-01280; add some relations for other characters.
(U-00020CAA): Use `->denotational' and `->subsumptive'.
(U-00020C99): Apply new conventions for glyph granularity.
(M-03617): Add `<-denotational' for U-00020C99; unify IU+20C99,
MJ032252 and KOSEKI-041570.
(M-03618): Unify U-00020C9A; apply new conventions for glyph
granularity.
(U+555E): Add `<-denotational@usage' for BUCS+555E and A2-DJT-01382;
add `sound@ja/on/{kan|go}'; unify DJT-01382; add some relations for
other characters.
(U+55AB): Add `<-denotational@usage' for BUCS+55AB.
(UU+55AB): Unify DJT-01422.
(U+5665): Add `<-denotational@usage' for BUCS+5665; apply new
conventions for glyph granularity.
(BUCS+5435): New abstract node.
(BUCS+5440): New abstract node; unify A2-DJT-01221.
(BUCS+5443): New abstract node; unify A2-DJT-01223.
(A2-DJT-01232): New abstract node.
(BUCS+54AC): New abstract node; unify A2-DJT-01280.
(A2-DJT-01382): New abstract node.
(BUCS+55AB): New abstract node; unify A2-DJT-01422.
(BUCS+5665): New abstract node; unify A2-DJT-01520.
(BUCS+555E): New abstract node; use `<-denotational' for A2-DJT-01382.