Log Message:
Update to 2.64

Upstream changes:
2.64 2017-04-23
    - Update some POD
    - No functional changes from 2.63_001 dev release

2.63_001 2017-04-17
    - Add no_cache option to new method following
      discussion at http://www.perlmonks.org/?node_id=1188065

2.62 2017-01-08
    - Add rlib to TEST_REQUIRES in Makefile.PL to avoid some
      cygwin test failures