title: json_decode returns false if a value has leading zeros
body: <h2>Description:</h2>
  
  <p>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.</p>
  
  <p>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.</p>
  
  <h2>Reproduce code:</h2>
  
  <pre><code>&lt;?php
  
  $payload = &lt;&lt;&lt;payload
  {
    "test" : 06
  }
  payload;
  
  if(!$obj = json_decode($payload)) die("Problems on JSON Parsing the json_decode() function     has returned false");
  
  print_r($obj);
  </code></pre>
  
  <h2>Expected result:</h2>
  
  <pre><code>stdClass Object ( [test] =&gt; 6 )
  </code></pre>
  
  <h2>Actual result:</h2>
  
  <pre><code>Problems on JSON Parsing the json_decode() function has returned false
  </code></pre>
  
  <h2>My problem:</h2>
  
  <p>This isn't quite JSON as explained <a href="https://bugs.php.net/bug.php?id=50286" rel="nofollow">here</a>. I can't really control what my user sends me, and can't tell them to be so specific as to trim leading zeros.</p>
  
  <p>How can I trim zeros before feeding the payload into json_decode?</p>