Saving cmp rounds

[valli0x]

I cant save cmp/keygen round. Some structures have variables that are not exported(pkg/pedersen Parameters).
We can add MarshalBinary and UnmarshalBinary methods and use the cbor package to save rounds.

We can use the RAFT protocol and multiple nodes to creating a pair of key and we can save rounds after each message. I think this is more fault tolerance.