Add serialization / deserialization functions for MRD messages

[wuerflts]

The MRD main repo was extended in a commit with functions to directly serialize and deserialize MRD objects from bytestreams. This enables very elegant short examples like the streamingreco and eliminates the need to replicate code for handling this task in applications. I did not find an equivalent in this library and I believe it should be extended with that functionality.

[naegelejd]

Resolved in #82