surprising the boxed values leak in `getCache()`

[stefanpenner]

I was abit surprised that boxed values leaked out when using getCache(). I would have assumed this would only happen via something more explicit, maybe model.boxValues().getCache()

[jhusain]

Valid point. The assumption is that this method will only be used to serialize state (in which case you'd want to preseve any metadat). That could perhaps be better reflected in the name of the method.