Generic cloner interface

[csviri]

Currently we can setup a objectMapper in configuration, where now this is used only for cloning custom resources (serializing and de-serializing POJOs):

https://github.com/java-operator-sdk/java-operator-sdk/blob/5431289871baaf221745cbf7e522b70f7e69c9e2/operator-framework-core/src/main/java/io/javaoperatorsdk/operator/api/config/ConfigurationService.java#L82-L90

The goal of this issue is to generalize this interface and have cloner interface in place, so not just sub-classes of object mappers can be provided.

[metacosm]

Do we really think there'll be other cloner implementations, though?

[csviri]

To run the Operator using Kotlin required different implementation. Basially a different object mapper. So the idea is that if we need already different alternatives and it's quite easy to make this generically replacable this way, it felt a little semly to just narrow the possibilities to object mapper.