Description:
------------
When parsing a JSON Payload containing integers or floats with leading 
zeros as values which haven't been escaped using double quotes, 
json_decode() returns false.

Even thought leading zeros are ( most of the times ) irrelevant for 
integers, the function should at least trim the zeros out and not fail 
the entire decoding process. JSON returned from some Java JSON 
generators come with integers containing leading zeros and not escaped 
by double quotes.

Reproduce code:
---------------
<?php

$payload = <<<payload
{
  "test" : 06
}
payload;

if(!$obj = json_decode($payload)) die("Problems on JSON Parsing the json_decode() function has returned false");

print_r($obj);

Expected result:
----------------
stdClass Object ( [test] => 6 )

Actual result:
--------------
Problems on JSON Parsing the json_decode() function has returned false