Update to 1.48

Upstream changes:
1.48 - 2013-05-06T04:47:00Z
    * Fixed test failure with versions of Pod::Simple lower than 3.24. Thanks
      to Martin Holste and Tatsuhiko Miyagawa for the reports.

1.47 - 2013-05-05T03:14:25Z
    * Fixed failing test on Pod::Simple 3.27 and higher.

1.46 - 2013-02-16T19:46:17Z
    * Fixed a crash when `all_pod_files_ok()` finds no files to test. Thanks
      to H.Merijn Brand.
    * Switched from custom file searching code to File::Find. Suggested by
      H.Merijn Brand.
    * Fixed failing test on Pod::Simple 3.24.

(wen)