p5-Unicode-Collate: update to 1.21.

1.21  Sat Nov  4 10:49:19 2017
    - mklocale: [rt.cpan.org #121664] . removed from @INC (take 2)
    - DUCET is updated (for Unicode 9.0.0) as Collate/allkeys.txt.
      * Please notice that allkeys.txt will be overwritten if you have had
        other allkeys.txt already.
    - The default UCA_Version is 34.
    - added tangut.t in t.
    - Locale/*.pl and CJK/Korean.pm are updated.

1.20  Fri Nov  3 11:50:21 2017
    - XS: [rt.cpan.org #121664] . removed from @INC
    - U::C::Locale newly supports locales: dsb, lkt.

(wiz)