Serialization techniques and libraries

Starting from this commit I begun experimenting with an injectable serialization mechanism. The first implementation, of course, being standard java serialization, I also tried using protostuff, the library based on google protocol buffers.

Protostuff vs Java Serialization

Protostuff has showed really interesting performance improvements (3/4x faster in deserialization) which is of course not suprising but remember we are talking about very very small times. Java Serialization doesn't require any external library, which is fine, but the real selling point of Protostuff is that, with the Protostuff-runtime package objects don't have to be mapped as messages and don't need to implement any interface, not even Serializable. None. Real POJOs. We have a winner, here ;)