Updated p5-Ref-Util to 0.203.

0.203    2017-05-14 10:55:51+02:00 Europe/Paris

        * Rename $REF_UTIL_IMPLEMENTATION environment variable to
          $PERL_REF_UTIL_IMPLEMENTATION (suggested by ether++)

0.202    2017-05-14 10:39:52+02:00 Europe/Paris

        * Use of the Pure-Perl implementation can now be forced at runtime by
          setting either $Ref::Util::IMPLEMENTATION or
          $ENV{REF_UTIL_IMPLEMENTATION} to "XS"
        * Fix is_*_formatref() error messages (reported by tobyink, #38)
        * Speed enhancements for is_*_formatref() on 5.8+
        * Restore 5.6 and 5.8 compatibility
        * PP behaviour now matches XS for \v1.2.3 and \sub {}
        * Updated documentation to reflect the PP/XS split

0.201    2017-05-12 15:42:54+02:00 Europe/Paris

        * Fix space/tab issue in Makefile (srezic, ether)
        * Don't use DynamicPrereqs for unrelated Makefile.PL snippet (ether)

0.200    2017-05-12 10:14:26+02:00 Europe/Paris

        * Reimplement in pure Perl, with a dynamic dependency on a new
          Ref::Util::XS module that contains the fast XS implementation.
          ether++ for the Dist::Zilla wrangling.

(wiz)