Log Message:
Update to 4.00

Upstream changes:
4.00 2018-12-07
    - production release

3.99_01 2018-12-03
    - BACKWARD INCOMPATIBILITY:
      As JSON::XS 4.0 changed its policy and enabled allow_nonref
      by default, JSON::PP also enabled allow_nonref by default

    - implement allow_tags that was introduced by JSON::XS 3.0
    - add boolean_values that was introduced by JSON::XS 4.0
    - allow literal tags in strings in relaxed mode, as JSON::XS 3.02 does
    - allow PERL_JSON_PP_USE_B environmental variable to restore
      old number detection behavior for compatibility
    - various doc updates