message: Update block header to JSON
diff: @@ -167,6 +167,11 @@ UniValue blockheaderToJSON(const CBlockIndex* blockindex)
  CBlockIndex *pnext = chainActive.Next(blockindex);
  if (pnext)
  result.push_back(Pair("nextblockhash", pnext->GetBlockHash().GetHex()));
  +
  + result.push_back(Pair("flags", strprintf("%s%s", blockindex->IsProofOfStake()? "proof-of-stake" : "proof-of-work")));
  + result.push_back(Pair("proofhash", blockindex->hashProof.GetHex()));
  + result.push_back(Pair("modifier", blockindex->nStakeModifier.GetHex()));
  +
  return result;
  }
  