Improving Routes, when an api method has only one parameter mapped to request body, allow it to be parsed directly from the request body

For example if our api method is

```php
    /**
     * Custom Class Parameter
     *
     * @param int    $id
     * @param Author $author
     *
     * @return Author
     */
    function putAuthor($id, Author $author)
    {
        return $author;
    }
```

before this commit only way to pass the data is with this body

```json
{
    "author":  {
        "name": "Arul",
        "email": "arul@luracast.com"
    }
}
```

This commit allows to accept the following request too along with the above

```json
{
  "name": "Arul",
  "email": "arul@luracast.com"
}
```

Discussed today on #185
Improved Resources, arrays and objects can now be mapped to the request body, when they are the only parameter for body