Auto validate JSONConverter objects

[hamidonos]

Situation

Currently there is no way to automatically let the JSONConverter validate deserialized objects.

You'd have to validate the objects manually after creation which is error-prone.

Wanted

The JSONConverter should automatically handle validation (similar to how Spring Bean Validation would work)

Solution

Idea:

Create a interface like JSONConvertable which defines a method called validate()

Inside the JSONConverter refactor the fromJson method so that It looks like this

`public T fromJSON(Class clazz, String json) ...

and call the validate() method automatically

[KYash03]

PR: #3890