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

Add mappings between CJK Ext B and CNS 11643 plain 7.
(U-00028EF4): Use `->denotational' instead of `->subsumptive'.
(U-00028F2A): Use `->subsumptive' to separate representative nodes.
(U+96A6): Likewise.
(U+96AB): Use `->denotational' to separate representative nodes.
(U-00028F5D): Use `->subsumptive' to separate representative nodes.
(U+96B5): Likewise.
(U-00028F73): Likewise.
(U-00028F75): Use `ideographic-radical@ucs' instead of
`ideographic-radical'; add `ideographic-radical@cns'; delete
`ideographic-strokes' and `total-strokes'.