implement serialize and deserialise

[omershlo]

The purpose of the code in KMS is to take a cryptographic protocol and to construct the actual messages that are supposed to be send among the participants.

• In order.
• without breaking the cryptography.
• Minimizing the round trips as much as possible

0. what is the best way to serialize / desialize in this case?
1. take the output messages from each protocol (keygen, sign, rotate, chain code etc) and serialize them
2. take the input messages from each protocol and deserialize them.