Implementation of AuthorityRound

This may be updated because it is incomplete. It should provide overal concept what needs to be ported from parity (open ethereum)

Diagram .bmp
https://swarm-gateways.net/bzz:/0f7a8602140983d25a9ac69349d64790105149d9eefd5bff05637c2bfb79cd01/AuraAuthorityRound.bmp Diagram .graphml
https://swarm-gateways.net/bzz:/c14975c573ebfaacad90af5a350ed75f57ad0084c78fc5c2526474bdbcb4b352/AuraAuthorityRound.graphml