title: combine freezed & hive
body: <p>I'm searching for a solution to combine <a href="https://pub.dev/packages/freezed" rel="noreferrer">freezed</a> and <a href="https://pub.dev/packages/hive" rel="noreferrer">hive</a> packages.
  For example like that:</p>
  <pre><code>@freezed
  abstract class Person extends HiveObject with _$Person {
    @HiveType(typeId: 0)
    factory Person({@HiveField(0) String name, @HiveField(1) int age}) = _Person;
  }
  </code></pre>
  <p>I know that this is not possible out of the box, but I think you know what I want to achieve. What would be the best way to implement freezed with hive?</p>
  <p>The only solution that I can currently think of is to store the json-String which is generated by freezed in hive. But I hope there is a better solution.</p>