Added Java API for and made Scala API more flexible (fixes #661)

[akara]

Allows independently accessing matValue

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[akara]

Based on the comments, I'm starting to think we should not have this abstraction at all. No abstraction is better than a bad abstraction. I'll submit a separate PR making the case objects accessible from Java land. This way you can use ActorLookup to obtain the MatValue directly. That would allow you to look up the actor by name. I can't call ActorLookup from inside Unicomplex as that creates a circular dependency. We'd need to use a the squbs-patterns package to deal with this. Let me put this PR on hold and deal with the simple one of making case objects accessible to get customer case resolved.

[akara]

In order to have an ActorLookup behavior, we best want to use ActorLookup itself.

[akara]

Closing this based on comments. We should do better integration with ActorLookup for this instead of forcing the API at this level.