handle different adversarial settings

[omershlo]

The code currently assumes:

1. all n refresh message arrive
2. If 1 out of n messages fails the test the protocol fails. Therefore in the protocol we simply take the first t+1 refresh messages after we checked all n messages are valid. In practice we need to take the first t+1 messages of parties that passed all checks (doesn't have to be indices 1...t+1)

We need to add support for the case where some parties are malicious, meaning that we have some k honest parties ,t<k<n, and that the malicious parties can attack any party (adversary is not necessarily control indices k+1...n for example)