message: Add dummy coinstake tx in the block
diff: @@ -143,6 +143,9 @@ std::unique_ptr<CBlockTemplate> BlockAssembler::CreateNewBlock(const CScript& sc
  // Add dummy coinbase tx as first transaction
  pblock->vtx.emplace_back();
  + // Add dummy coinstake tx as second transaction
  + if(fProofOfStake)
  + pblock->vtx.emplace_back();
  pblocktemplate->vTxFees.push_back(-1); // updated at end
  pblocktemplate->vTxSigOpsCost.push_back(-1); // updated at end
  