Add mappings between CJK Ext B and CNS 11643 plain 7.

Add mappings between CJK Ext B and CNS 11643 plain 7.
(U+9093): Add `sound@ja/on'; unify JC3-82C4; add `<-simplified@CN' for
G1-354B.
(U+90F0): Use `->subsumptive'.
(U+90F8): Add `<-simplified@CN' for U+9132.
(RUI6-E074): New character.
(U-0002874D): Use `->subsumptive' to separate representative nodes.
(U+9127): Add `sound@ja/on/kan' and `sound@ja/on/go'; use
`->subsumptive' to separate representative nodes; integrate JC3-68B0.
(U+9128): Use `->denotational'.
(U+9129): Use `->denotational'.
(U+912E): Use `->subsumptive' to separate representative nodes.
(U+48DF): Use `->denotational' to separate representative nodes.
(U-00028790): New character.
(U-00028793): Use `->subsumptive'.
(U+9133): Use `->subsumptive' to separate representative nodes.
(U-000287AB): Likewise.
(U+48E2): Likewise.
(U+9138): Use `->denotational'.
(U+9139): Likewise.
(U-000287A3): New character.
(U-000287B2): New character.
(U+913A): Use `->denotational'.
(U+913B): Use `->subsumptive'.
(U+913E): Use `->denotational' and `->subsumptive'.
(U+9142): Add `<-simplified@CN' for UU+9147.
(U+9147): Use `->subsumptive' to separate representative nodes.
(U+9148): Use `->subsumptive'.
(U-000287E5): New character.
(U+48E3): Use `->subsumptive' to separate representative nodes.
(U+48E4): Likewise.