Include ed25519 relay id keys in the consensus

Proposal 220 specifies how ed25519 id keys should be encoded in the consensus, but the change has not been implemented yet.

This is a problem in the next gen HS design, since prop224 specifies that the HSDir hash ring should be formed using the relay ed25519 keys, but these are not in the consensus which means that the service and the clients need to fetch all the microdescriptors before getting an accurate picture of the hash ring. Uploading or fetching HS descriptors without having all the relay microdescriptors can lead to hash ring desynch and reachability failures.