[Serializer] Name Converter

| Q                | A
| --------------- | ---
| Doc fix?      | no
| New docs? | yes symfony/symfony#13120
| Applies to   | 2.7

This is the documentation for the Serializer Name Converter feature.
Yeah, you're correct. Then we should maybe do something like:

````php
// remove org_ prefix
return substr($propertyName, 0, 4) === 'org_'
    ? substr($propertyName, 4)
    : $propertyName;
````