JSON::MaybeXS->new requires 1.001000

e.g. see
http://www.cpantesters.org/cpan/report/ed53d798-7b92-11e4-8474-604a5d97b750
Dist-Zilla-Plugin-CheckIssues-0.007

          - bump up required version of JSON::MaybeXS, to ensure necessary
            interfaces are available