JSON::PP: Synch with CPAN version 4.12

From Changes: Call unimport overload first to silence warnings.
(makamaka/JSON-PP#76, haarg++)

Committer: To keep 'make test_porting' happy, run:
    cd t; ./perl porting/regen.t; cd -
    ./perl -Ilib Porting/makemeta -j

META.json

@@ -120,5 +120,5 @@
       }
    },
    "version" : "5.037005",
-   "x_serialization_backend" : "JSON::PP version 4.11"
+   "x_serialization_backend" : "JSON::PP version 4.12"
 }

Porting/Maintainers.pl

@@ -683,7 +683,7 @@ package Maintainers;
     },
 
     'JSON::PP' => {
-        'DISTRIBUTION' => 'ISHIGAKI/JSON-PP-4.11.tar.gz',
+        'DISTRIBUTION' => 'ISHIGAKI/JSON-PP-4.12.tar.gz',
         'FILES'        => q[cpan/JSON-PP],
     },
 

cpan/JSON-PP/lib/JSON/PP.pm

@@ -14,7 +14,7 @@ use JSON::PP::Boolean;
 use Carp ();
 #use Devel::Peek;
 
-$JSON::PP::VERSION = '4.11';
+$JSON::PP::VERSION = '4.12';
 
 @JSON::PP::EXPORT = qw(encode_json decode_json from_json to_json);
 

cpan/JSON-PP/lib/JSON/PP/Boolean.pm

@@ -3,14 +3,15 @@ package JSON::PP::Boolean;
 use strict;
 require overload;
 local $^W;
+overload::unimport('overload', qw(0+ ++ -- fallback));
 overload::import('overload',
     "0+"     => sub { ${$_[0]} },
     "++"     => sub { $_[0] = ${$_[0]} + 1 },
     "--"     => sub { $_[0] = ${$_[0]} - 1 },
     fallback => 1,
 );
 
-$JSON::PP::Boolean::VERSION = '4.11';
+$JSON::PP::Boolean::VERSION = '4.12';
 
 1;