• PERL_JSON_BACKEND now accepts Cpanel::JSON::XS as well
  
• tweaked tests to support various backends
  
• made convert_blessed_universally (for Perl 5.18+) and
  support_by_pp less harmful
  
• fixed N/A exit code in Makefile.PL (bulk88)
  
• various doc patches from gregoa, topaz, zoffix, singingfish,
  yanick, dsteinbrunner, Toby Inkster
  
• removed duplicated tests
  
• removed base.pm dependency
  
• updated backportPP with JSON::PP 2.91_01