Update to 1.52

Upstream changes:
1.52    2013-05-21
    - Add t/style-trailing-space.t.
        - Got rid of trailing space.
    - Convert to t/cpan-changes.t .

1.51    2013-05-11
    - Sort the XML namespaces before outputting.
        - became broken in perl-5.18.0-RC1.

(wen)