Add a project for serialization based on AVRO

[MASES Public Developers Team]

The new KEFCore.SerDes project was added as base reference; it is important to add a project, based on AVRO, to add the binary serialization used from Apache Kafka so external applications can attach to the bus and use the information retrieving the schema from Schema Registry.

Originally posted by @masesdevelopers in #86 (comment)