Add JSON.pm to third_party

third_party/JSON/JSON-2.59/MANIFEST

+Changes
+eg/bench_decode.pl
+eg/bench_encode.pl
+lib/JSON.pm
+lib/JSON/backportPP.pm
+lib/JSON/backportPP/Boolean.pm
+lib/JSON/backportPP/Compat5005.pm
+lib/JSON/backportPP/Compat5006.pm
+Makefile.PL
+MANIFEST
+META.yml                        Module meta-data (added by MakeMaker)
+README
+t/00_load.t
+t/00_pod.t
+t/01_utf8.t
+t/02_error.t
+t/03_types.t
+t/06_pc_pretty.t
+t/07_pc_esc.t
+t/08_pc_base.t
+t/09_pc_extra_number.t
+t/10_pc_keysort.t
+t/11_pc_expo.t
+t/12_blessed.t
+t/13_limit.t
+t/14_latin1.t
+t/15_prefix.t
+t/16_tied.t
+t/17_relaxed.t
+t/18_json_checker.t
+t/19_incr.t
+t/20_unknown.t
+t/21_evans_bugrep.t
+t/22_comment_at_eof.t
+t/99_binary.t
+t/_unicode_handling.pm
+t/e00_func.t
+t/e01_property.t
+t/e02_bool.t
+t/e03_bool2.t
+t/e04_sortby.t
+t/e05_esc_slash.t
+t/e06_allow_barekey.t
+t/e07_allow_singlequote.t
+t/e08_decode.t
+t/e09_encode.t
+t/e10_bignum.t
+t/e11_conv_blessed_univ.t
+t/e12_upgrade.t
+t/e13_overloaded_eq.t
+t/e14_decode_prefix.t
+t/e15_tie_ixhash.t
+t/e16_incr_parse_fixed.t
+t/e90_misc.t
+t/x00_load.t
+t/x02_error.t
+t/x12_blessed.t
+t/x16_tied.t
+t/x17_strange_overload.t
+t/xe01_property.t
+t/xe02_bool.t
+t/xe03_bool2.t
+t/xe04support_by_pp.t
+t/xe05_indent_length.t
+t/xe08_decode.t
+t/xe10_bignum.t
+t/xe11_conv_blessed_univ.t
+t/xe12_boolean.t
+t/xe19_xs_and_suportbypp.t
+t/xe20_croak_message.t
+META.json                                Module JSON meta-data (added by MakeMaker)