Investigate replacing bincode

It is not clear how healthy the bincode project actually, for example when the 2.0 release candidates will achieive general availability or if Serde support remains a first class concern.

We should probably investigate viable alternatives like:

• postcard which actually started out as a fork of bincode IIRC but has a focus on embebbed usage which is not a good fit for us.
• flexbuffers which uses a similar format as flatbuffers and can interoperate with Serde.